Add GLES32 class templates

- Added a script that takes the #defines in gl2/3.h and formats them
  for use in the Java template.

- Generated GLES32.spec using glgen2.

- Added full support for void* in glgen. It wasn't previously
  necessary since the apis were using GLvoid instead.

- Created the GLES32 header stubs. Added stubs for GLES32 functions
  that couldn't be handled by the code generator. Added checks in the
  checks.spec file where appropriate.

- Generated the GLES32 class and JNI.

Change-Id: Ifc8512ed56af75bbc3e7ec2ea1377895201d5325