NOISSUE Fix/Update Link checker script and fix dead links (#255)

* NOISSUE [DevelopmentTools] Fix and extend link availability check

Add the following features/fix the following mistakes:

* Fake browser User-Agent in the header as some sites block scripts
* Add parameter to search html files by pattern and default it to
  'nl/' directories
* Add parameter to exclude certain project names and let it default to
  'org.jcryptool.core.nl' as this uses another link format.
* Add parameter for an ignore file. The ignore file can contain links
  which are queried nevertheless. But if they fail they will not be
  counted as errors. A specific reason can be specified so it will only
  count as ignored if that reason is matched.
  It defaults to ./ignore_links.txt
  Add the ignored information to the summary
* Add meaningful return value: 0 if all links reachable or ignored, 1 if
  any link was not reachable (failed).
* Fix timeout case not being counted as timeout
* Improve formatting

* NOISSUE [OnlineHelp] Fix/Update dead links

org.jcryptool.core.help/nl/de/help/users/algorithms/signature/toc.html

@@ -30,7 +30,7 @@ <h2>Über Signaturen</h2>
 	<p>Digitale Signaturen sind eine Standardkomponente der meisten kryptografischen Protokoll-Suiten. Sie werden häufig für Software-Verteilung, Finanztransaktionen, Vertragsverwaltungssoftware und in weiteren Fällen verwendet, in denen es wichtig ist, Fälschungen oder Manipulationen zu erkennen.
 	<b>Digitale</b> Signaturen werden oft verwendet, um <b>elektronische</b> Signaturen zu implementieren.</p>
 
-	</p>Das folgende Bild zeigt eine visuelle Darstellung des Signier- und Verifizierungsprozesses (<a href="https://commons.wikimedia.org/wiki/File:Digital_Signature_diagram_de.svg">Diagramm Digitale Signatur</a> von Acdx, lizenziert unter <a href="https://creativecommons.org/choose/zero/">CC0</a>).</p>
+	</p>Das folgende Bild zeigt eine visuelle Darstellung des Signier- und Verifizierungsprozesses (<a href="https://commons.wikimedia.org/wiki/File:Digital_Signature_diagram_de.svg">Diagramm Digitale Signatur</a> von Acdx, lizenziert unter <a href="https://creativecommons.org/licenses/by-sa/3.0/deed.de">CC BY-SA 3.0</a>).</p>
 
 	<img src="PLUGINS_ROOT/org.jcryptool.core.help/$nl$/single/img/1500px-DSA-diagram.png" width="85%" alt="Visuelle Darstellung des Signier- und Verifizierungsprozesses" />
 

org.jcryptool.core.help/nl/de/help/users/cryptology/crypto_methods.html

@@ -9,7 +9,7 @@
 
 <h1>Kryptografische Verfahren</h1>
 
-<P>Britannica (<a target="_blank" href="http://www.britannica.com">http://www.britannica.com</a>) beginnt seine Definition folgendermaßen:</P>
+<P>Britannica (<a target="_blank" href="https://www.britannica.com">http://www.britannica.com</a>) beginnt seine Definition folgendermaßen:</P>
 
 <P><B>Kryptologie</B> (vom Griechischen <I>kryptós, </I>"versteckt," und <I>lógos, </I>"Wort") ist die Wissenschaft von sicherer (allgemein geheimer) Kommunikation. Diese Sicherheit bedingt, dass die berechtigten Teilnehmer in der Lage sind, eine Nachricht mit Hilfe eines Schlüssels in einen Geheimtext zu transferieren und zurück. Obwohl der Geheimtext für jemand ohne den geheimen Schlüssel unlesbar und unfälschbar ist, kann der berechtigte Empfänger entweder das Chiffrat entschlüsseln, um die den verborgenen Klartext wieder zu erhalten, oder verifizieren, dass die Nachricht aller Wahrscheinlichkeit nach von jemand geschickt wurde, der den richtigen Schlüssel besaß.</P>
 

org.jcryptool.core.help/nl/de/help/users/cryptology/toc.html

@@ -16,7 +16,7 @@ <h1>Kryptologie</h1>
 	<p>Weitere Informationen zum Einstieg finden Sie unter:</p>
 	<ul>
 	<li><a target="_blank" href="https://de.wikipedia.org/wiki/Kryptografie">https://de.wikipedia.org/wiki/Kryptografie</a></li>
-	<li><a target="_blank" href="https://www.cryptool.org/images/ctp/documents/CT-Book-de.pdf">Das CrypTool-Buch</a></li>
+	<li><a target="_blank" href="https://www.cryptool.org/download/ctb/CT-Book-de.pdf">Das CrypTool-Buch</a></li>
 	</ul>
 
 <br/>

org.jcryptool.core.help/nl/de/help/users/games/toc.html

@@ -10,7 +10,7 @@
 <h1>Spiele</h1>
 
 	<p>Das JCT-Hauptmenü <strong>Spiele</strong> (in der Standard-Perspektive) hat 3 Einträge. Alle 3 Spiele haben Krypto-Bezug. Beispielsweise das 
-    <a href="http://org.eclipse.ui.intro/showHelpTopic?id=/org.jcryptool.games.numbershark/$nl$/help/gettingstarted/NumberSharkHelp-Tutorial.html">Zahlenhai</a>-Spiel, das Schülern spielerisch helfen kann, Teiler und Primzahlen besser zu verstehen. Hier wurde Lernstoff didaktisch verpackt.</p>
+    <a href="PLUGINS_ROOT/org.jcryptool.games.numbershark/$nl$/help/toc.html">Zahlenhai</a>-Spiel, das Schülern spielerisch helfen kann, Teiler und Primzahlen besser zu verstehen. Hier wurde Lernstoff didaktisch verpackt.</p>
 
 </p></br></br>
 </body>

org.jcryptool.core.help/nl/de/single/RSA.html

@@ -47,7 +47,7 @@ <h2>Quellen</h2>
 
 <ul>
 	<li><a target="_blank" href="https://de.wikipedia.org/wiki/RSA-Kryptosystem" >[1] Wikipedia: RSA-Kryptosystem</a></li>
-	<li><a target="_blank" href="https://www.cryptool.org/assets/img/ctp/documents/CT-Book-en.pdf" >[2] Das CrypTool-Buch</a></li>
+	<li><a target="_blank" href="https://www.cryptool.org/download/ctb/CT-Book-de.pdf" >[2] Das CrypTool-Buch</a></li>
 	<li><a target="_blank" href="https://eprint.iacr.org/2003/159.pdf" >[3] Paixao: "An efficient variant of the RSA cryptosystem", eprint paper, 2003</a> </li>
 	<li><a target="_blank" href="https://hovav.net/ucsd/dist/survey.pdf" >[4] Boneh and Shacham: "Fast Variants of RSA", 2002</a></li>
 	<li><a target="_blank" href="https://de.wikipedia.org/wiki/Optimal_Asymmetric_Encryption_Padding" >[5] Wikipedia: Optimal Asymmetric Encryption Padding</a></li>

org.jcryptool.core.help/nl/en/help/users/algorithms/signature/toc.html

@@ -29,7 +29,7 @@ <h2>About signatures</h2>
 	<p>Digital signatures are a standard element of most cryptographic protocol suites, and are commonly used for software distribution, financial transactions, contract management software, and in other cases where it is important to detect forgery or tampering.
 	<b>Digital</b> signatures are often used to implement <b>electronic</b> signatures.</p>
 
-	</p>The following image gives a visual representation of the signing and verification processes (<a href="https://commons.wikimedia.org/wiki/File:Digital_Signature_diagram.svg">Digital Signature Diagram</a> by Acdx, licensed under <a href="https://creativecommons.org/choose/zero/">CC0</a>).	</p>
+	</p>The following image gives a visual representation of the signing and verification processes (<a href="https://commons.wikimedia.org/wiki/File:Digital_Signature_diagram.svg">Digital Signature Diagram</a> by Acdx, licensed under <a href="https://creativecommons.org/licenses/by-sa/3.0/deed.en">CC BY-SA 3.0</a>).	</p>
 
 	<img src="PLUGINS_ROOT/org.jcryptool.core.help/$nl$/single/img/1500px-DSA-diagram.png" width="85%" alt="Visual representation of the signing and verification processes" />
 

org.jcryptool.core.help/nl/en/help/users/cryptology/crypto_methods.html

@@ -9,7 +9,7 @@
 
 <h1>Cryptographic Mechanisms</h1>
 
-<P>Britannica (<a target="_blank" href="http://www.britannica.com">http://www.britannica.com</a>) starts its definition with:</P>
+<P>Britannica (<a target="_blank" href="https://www.britannica.com">http://www.britannica.com</a>) starts its definition with:</P>
 
 <P><B>Cryptology</B> (from the Greek <I>kryptós, </I>"hidden," and <I>lógos, </I>"word") is the science of secure (generally secret) communications. This security obtains from legitimate users, the transmitter and the receiver, being able to transform information into a cipher by virtue of a key &ndash; <I>i.e.,</I> a piece of information known only to them. Although the cipher is inscrutable and often unforgeable to anyone without this secret key, the authorized receiver can either decrypt the cipher to recover the hidden information or verify that it was sent in all likelihood by someone possessing the key.</P>
 

org.jcryptool.core.help/nl/en/help/users/cryptology/toc.html

@@ -16,7 +16,7 @@ <h1>Cryptology</h1>
 	<p>Further information to start with can be found at:</p>
 	<ul>
 	<li><a target="_blank" href="https://en.wikipedia.org/wiki/Cryptography">https://en.wikipedia.org/wiki/Cryptography</a></li>
-	<li><a target="_blank" href="https://www.cryptool.org/images/ctp/documents/CT-Book-en.pdf">The CrypTool Book</a></li>
+	<li><a target="_blank" href="https://www.cryptool.org/download/ctb/CT-Book-en.pdf">The CrypTool Book</a></li>
 	</ul>
 
 <br/>	

org.jcryptool.core.help/nl/en/help/users/games/toc.html

@@ -10,7 +10,7 @@
 	<h1>Games</h1>
 
 	<p>The JCT main menu <strong>Games</strong> (in the Default Perspective) has 3 entries. All 3 games have crypto reference. For example the 
-    <a href="http://org.eclipse.ui.intro/showHelpTopic?id=/org.jcryptool.games.numbershark/$nl$/help/gettingstarted/NumberSharkHelp-Tutorial.html">Number Shark</a> game that can help students to better understand divisors and prime numbers in a playful way. Here, learning material was didactically packed.</p>
+    <a href="PLUGINS_ROOT/org.jcryptool.games.numbershark/$nl$/help/toc.html">Number Shark</a> game that can help students to better understand divisors and prime numbers in a playful way. Here, learning material was didactically packed.</p>
 
 
 </body>

org.jcryptool.core.help/nl/en/help/users/visualizations/toc.html

@@ -35,7 +35,7 @@ <h1>Visualizations</h1>
     <p> </br> </p>
 	<p>More cryptographic algorithms in JCT can be found at</p>
 	<ul>
-        <li><a href="./../algorithms/toc.html">Algorithms main menu</a> &ndash;  Performs classic and modern algorithms without visualizing them (in the <a href="http://org.eclipse.ui.intro/showHelpTopic?id=/org.jcryptool.core.help/$nl$/help/users/general/perspective_default.html&amp;embed=false;">Default Perspective</a>)</li>
+        <li><a href="./../algorithms/toc.html">Algorithms main menu</a> &ndash;  Performs classic and modern algorithms without visualizing them (in the <a href="PLUGINS_ROOT/org.jcryptool.core.help/$nl$/help/users/general/perspective_default.html">Default Perspective</a>)</li>
         <li><a href="./../general/perspective_algorithm.html">Algorithm Perspective</a> &ndash;  Offers the algorithms from the crypto providers Bouncy Castle and FlexiProvider (only modern algorithms)</li>
     </ul>
 

org.jcryptool.core.help/nl/en/single/RSA.html

@@ -47,7 +47,7 @@ <h2>References</h2>
 
 <ul>
 	<li><a target="_blank" href="https://en.wikipedia.org/wiki/RSA_(cryptosystem)" >[1] Wikipedia: RSA (cryptosystem)</a></li>
-	<li><a target="_blank" href="https://www.cryptool.org/assets/img/ctp/documents/CT-Book-de.pdf" >[2] The CrypTool Book</a></li>
+	<li><a target="_blank" href="https://www.cryptool.org/download/ctb/CT-Book-en.pdf" >[2] The CrypTool Book</a></li>
 	<li><a target="_blank" href="https://eprint.iacr.org/2003/159.pdf" >[3] Paixao: "An efficient variant of the RSA cryptosystem", eprint paper, 2003</a> </li>
 	<li><a target="_blank" href="https://hovav.net/ucsd/dist/survey.pdf" >[4] Boneh and Shacham: "Fast Variants of RSA", 2002</a></li>
 	<li><a target="_blank" href="https://en.wikipedia.org/wiki/Optimal_asymmetric_encryption_padding" >[5] Wikipedia: Optimal asymmetric encryption padding (OAEP)</a></li>

org.jcryptool.releng/helper/ignored_links.txt

@@ -0,0 +1,4 @@
+# Some weird error with the servers DH key
+https://secg.org/sec1-v2.pdf                         dh key too small
+# Not queryable by script.
+https://www.eetimes.com/document.asp?doc_id=1274550  timed out