Updated support to handling keys on Android, and a few improvements
Fixed an JNI call that was not keeping it's global ref and dying on ICS >
Ran the include what you use tool, made a lot of refactorings, fixed a lot of stuff

Removed the redundant GL20 static variables, removed some undefs that were annoying, added enum classes to the Pixmap family
and improved security against macros by duplicating the name inside the enum
Many improvements on the Linux OpenAL stack.

Rewrote a bunch of operations, added checks on most calls. The openAL backend should be merged
and used on all platforms as one thing.
fixed import and enum type
There's no need to generate gl.hpp anymore. Fixed a bug on gdx.cmake to get the correct variable for ANDROID_NDK
Merge branch 'master' of github.com:aevum/libgdx-cpp
Updated the iOS backend to the latest updateds
Refactored the IosOpenALMusic to use small chunks of data instead of the whole file

The openAL audio backend MUST BE merged in one thing. The ios and linux (and probably the android) backends are
identical now
Removed most of the unported code.
Changed the JsonReader class to be thread-safe
Merge branch 'master' of github.com:aevum/libgdx-cpp