Minor changes in README.md and templates/manifest.gjson

- Change credits to translators in README.md so it mentions all the
  translators and not only Alexander.
- Add bugs/beta version sections to README.md.
- Add author and homepage_url fields to manifest.gjson.

Change-Id: I4580ac64e43de5263586627e5d762d696a9c93b5

README.md

@@ -10,13 +10,31 @@ translating :)
 
 [![Crowdin](https://d322cqt584bo4o.cloudfront.net/translateselectedtext/localized.svg)](https://crowdin.com/project/translateselectedtext)
 
+## Bugs
+Please, report any bugs or feature sugestions at GitHub:
+[https://github.com/avm99963/translateselectedtext/issues](https://github.com/avm99963/translateselectedtext/issues)
+
+## Beta version
+As this extension has so many users, I've decided to upload a Beta version of
+the extension to the Chrome Web Store so I can test it before uploading any
+update to the stable version! This way I can make sure that the stable version
+of the extension is 100% bug-free.
+
+If you want to test the bleeding edge of this extension before everybody else,
+join the Google Group and download the extension (there may be bugs, you've been
+warned):
+
+- [Google Group](https://groups.google.com/g/gtranslator-beta)
+- [Translate Selected Text (Beta)](https://chrome.google.com/webstore/detail/translate-selected-text-b/pckjhlclhnnhdadoockkhgfkceeljnkg)
+
 ## Special thanks
 Special thanks to:
 * All the users who use the extension every day and who trust the model of
 developing simple extensions which do not request any privacy-breaking
 permissions.
-* Alexander Simkin for the Russian translation.
-* BrowserStack for allowing me to use their awesome services in order to test the extension in multiple versions of Chrome and in different operating systems.
+* All the users who [have contributed translations](https://crowdin.com/project/translateselectedtext/activity_stream). You rock!
+* BrowserStack for allowing me to use their awesome services in order to test
+the extension in multiple versions of Chrome and in different operating systems.
 
 ## More documents
 * [For developers working on the extension](docs/development.md)

templates/manifest.gjson

@@ -2,6 +2,8 @@
   "manifest_version": 2,
   "name": "__MSG_appName__",
   "description": "__MSG_appDescription__",
+  "author": "Adrià Vilanova Martínez (@avm99963)",
+  "homepage_url": "https://gerrit.avm99963.com/plugins/gitiles/translateselectedtext/",
   "version": "0",
   "version_name": "dirty",
   "permissions": [