implement a paperwallet generator

[truedat101]

Currently in progress in pieces:

• https://github.com/IoTone/QR-Code-generator/tree/master/d
• Complete QR code generator written in D paperwallet-d#2
• Repurpose this design for NEM/Symbol / TheShellProject paperwallet-d#1

I have reviewed the paper wallet generated by the new Symbol QR wallet generator. It's nice. It's printable. It fits in a wallet (literally). So while I don't think we need the full functionality, minimally, being able to generate HTML or raster image (I think an image is more secure than a complete html dump), or PDF, is useful. Really, you want to put the burden on the asset holder to handle their own security and not leave little dumps of insecurity on someone's server or PC.

[truedat101]

Some progress on this. I've got a basic port done. Since this isn't a top priority until a blockchain api exists, get back to this later. Could use about 8-15 hours of help on wrapping up that port of the QR code (fix the crash, finish porting one of the test cases, and maybe enhance the test to include generated QR codes). The port was not too tough, but I did a sloppy, straight C port. I didn't wrap the C library, but I just did the minimal rewrite. So its grimy and needs some D love.

[truedat101]

Once the QR code generator is done, the actual paper wallet code is easy as far as generating some HTML output that can be printed out. The crypto blockchain part is some work, but that really depends on a D library being available. I did some work on the paperwallet-eth to fix some bugs I found there, so the code is familiar. I have also looked at the QR generator stuff used by NEM / Symbol and it is nice in terms of what it does.