SH-2038 FIX -- [PUBLIC] Severe performance drop on MacBook Pros

EXP-997 FIX -- Significant FPS degradation in 2.8.0 Beta on Mac equipped ATI video card

* Disabled VBO's on mac to avoid stalls in renderer
* Placed valid data into the padding between triangles in the vertex buffer to remove uninitialized craziness
* Removed invalid rendering checks causing GL errors in debug mode

Reviewed by davep