texture() doesn't exist in glsl 100, it must use texture2D().

Some shader calculations are now pre-calculated because some math
functions doesn't exist in glsl 110.

Fix Android template with 1.5 raylib features (audio streaming, gestures)

clean up audio chiptunes support

... and switch from debug build to release

Trying to simulate Oculus Rift CV1 rendering without the device... for
Debug pourposes.

...on Android

Fix mistake in the make file

Moved all external libraries used by raylib to external folder inside
raylib src. Makefile has already been update and also the different
includes in raylib modules.