Merge pull request #2 from dkreuter/master

Removal of old code
Some minor syncing
Some syncing
Sync until and including tqaa
Last little sync before huge breaky patch
Merged Tesseract until SDL2 merge, welcome back cubescript

Tesseract is now merged to the point right before SDL2. Cubescript is reintegrated back into the codebase, handling shaders, console and later a few other things. Remove some old APIs (e.g. shader API) from Lua that are handled by cubescript now.
Initial SDL2 import
Another batch of Tesseract merges - OpenGL profiles are now supported
Another batch
We're in sync, also moved keymap to cubescript
Some cubescript commands, unify main.cpp a bit more with tesseract
sounds.cfg in cubescript, sync sound.cpp a bit
Texture blending in cubescript
default_map_settings is now cubescript as well as all commands from texture.cpp
Replace the silly lua cubescript command with a better one
Even better lua command - it's now possible to return strings and numbers from the Lua chunk and access them as lua command return values
Make it work the other way - a cubescript function callable from Lua that can return values (numbers and strings)
font.cfg