Revised font system

[dlamkins]

Fonts are currently bitmap fonts that were pregenerated. It would be preferable to use a system that can handle generating font atlases at runtime, can support better scaling support, support for additional character sets via fallback fonts, etc.

The ideal conversion would be to replace the current implementation with FontStashSharp. We'd want the result to be a mostly drop in replacement in terms of the visual result.

[dlamkins]

I've begun working on these improvements.

[agaertner]

How is this progressing? Are there any problems and can I help in anyway?

Otherwise, could we reconsider reopening #406 if FontSharp is not a priority? Gives a bit more variety in the meantime.

I have some ideas with fading from and to Krytan typeface to give a cool visual effect. :D

[real-zony]

Is there any update on this issue? I have replaced BitmapFont with FontStashSharp in my forked repository, which supports Chinese and works well. Of course, my code is only used to verify the support of Blish HUD for Chinese and the implementation of IME Helper. (Currently, there are no good ideas.)