C# library added

[fluiddot]

This is a simple C# lib with a ShortnameToUnicode method to get unicode strings from shortnames.

[caseyahenson]

@fluiddot nice work on this! With the release of 3.0, emoji strategy is now keyed by 'unicode' (which is actually base code point/file name) instead of shortname. Please account for this in your .map function in generate.js as well as in your .cs file.

Also note that previously the "shortname" key was not wrapped in a : where the attribute is now in that form, so you'll want to strip those out in your map as well.

Once that's done I'll go ahead and merge this.

[hackathi]

I resurrected this and re-posted it as #594. Most of the original Code by @fluiddot remained, but my version uses the new 3.0 structure and has slightly more functionality.

[fluiddot]

Closing this PR as it's updated in #594