gsdx ogl:
* uniform was wrongly set before the activation of the program (free driver only)
* Always use only 1 drawbuffer. Easier besides previous setup was wrong for convert:ps_main1

GLES trial (v3):
* add the cmake option GLES_API. Note library (libgles) are hardcoded for the moment
* Disable opengl check
* Disable gl_GetDebugMessageLogARB not supported!
* Emulate gl_DrawElementsBaseVertex, add manually the index offset (surely slow but work)
* Fix hundred of shader error (no implicit cast of integer to float...)
Unfortunately GLES doesn't support dual blending so no blend in hardware renderer. Otherwise it is fine




git-svn-id: http://pcsx2.googlecode.com/svn/trunk@5700 96395faa-99c1-11dd-bbfe-3dabce05a288