Documented IGlyphProvider and cleaned up settings a little, making it easier to add additional glyph providers in the future.
Also moved debug related stuff from computer.debug into top level category debug in settings, merged some other stuff into that.
Merge branch 'master' of github.com:MightyPirates/OpenComputers into master-MC1.7.10

Conflicts:
	src/main/scala/li/cil/oc/client/renderer/font/DynamicFontRenderer.scala
	src/main/scala/li/cil/oc/client/renderer/font/FontParserUnifont.java