* Fix DebugDraw shaders compilation
Pull request #2317 broke compilation of the DebugDraw shaders (vs_debugdraw_fill.sc, etc)
on the Intel mesa driver. Shaders with a version lower than 130 have no
support for uvec or ivec by default on OpenGL.
This patch detects when these shaders are present and bumps the version when appropriate.
* Removed the ivecs from the patch
It seems the ivecs are infact supported on versions lower than 130 on
OpenGL.