Note to self: melonDS changes

[andlabs]

http://melonds.kuribo64.net/board/thread.php?pid=389

Keeping this open until I settle everything in this thread.

[andlabs]

https://github.com/StapleButter/melonDS/tree/master/src/libui_sdl/libui

also CCing @StapleButter because why not

[msink]

#374