Merge w/ trunk: r52086-r52534 (As with last time, the game engine was not merged)

Merge w/ trunk: r51141-52085 (Important Note: gameengine and blenderplayer were not merged due to complex differences)

Added a WITH_CODE_COVERAGE option that works with clang and beginnings of a gpucov.py script that I will use to make sure I have tested all the new gpu code.

Merge w/ trunk: r50097-r51140 (also, I got ahead of myself and fixed a lot of warnings before committing)

GPU_SAFETY fix: Was asserting when switching to "material" view port mode.

OpenGL Usage Polcy fixes: glBlendFunc

Default value is GL_ALPHA/GL_ONE_MINUS_ALPHA.
No need to set this as blend function if that is what is needed.
Always return value to this if using a non-default blend function.

svn merge ^/trunk/blender -r50064:50096

"Pens Down" merge /w trunk r49015-r50064. Make clean patches for Google Summer of Code against trunk revision 50064.

Note: The new flag LIB_LOAD_ASYNC in the GE conflicted with trunks new LIB_LOAD_SCRIPTS, so I changed the value of ASYNC. So, heads up if these values has been saved in any .blend files!

Once again (see last merge note) it seems like node_draw.c had a bunch of wierd conflicts that make it look like it missed a merge or update. Not sure what is going on with that file.

Other parts of the merge had some difficulty resolving proper bracket nesting in places where it seems like the merge should have gone smoothly. Maybe that was KDiff3's fault? This reduces my confidence on if bugs were not introduced.

Added file view3d_composite.c to be the home of a small API needed to do complex GPUaspectfuncs that involve combining multiple layers.

The file is empty right now, but I wanted to include it before doing a merge in preparation for submitting the patch for the end of GSoC.

Some texture fixes and Clean up for GLES/GLSL

Added missing gpuImmediateFormat/gpuImmediateUnformat for knife tool and proportional edit

fixed warning about const qualifier on function parameter

Added missing gpuImmediateFormat/gpuImmediateUnformat for loopcut visualization.

There was a harmless errant backslash () at the end of the file that I removed.

Added missing gpuImmediateFormat/gpuImmediateUnformat for drawing certain kinds of bones.

Added missing gpuImmediateFormat_V3/gpuImmediateUnformat that was causing blenderplayer to crash.

stdint.h is not available in MSVC

Moving toward the new way of handling context. Not fleshed out, but merging to prevent against data loss (while it is still compiling!).

Switching Android GE from VA to VBO. VBO gives much better performance on Android.

Switching Blender Font texture from GL_CLAMP to GL_CLAMP_TO_EDGE, as there is no difference and previous in not supported by GLES.
It is a good idea to add texture api later.
Adding real mode for GLES