* Cleaned up vertex buffer allocation to guarantee allocation and deallocation using the same allocation methods from the same pools.
* Added new shader feature for atmospheric helpers in the absence of lighting.

Reviewed by davep.

Reviewed by davep.

SH-2565 Move resetVertexBuffer operation to a consistent location (also avoid redundant resetting of vertex buffers on detail switches).  Change assertion to a warning with count info.  Fix bytes pooled debug display.  Remove unused static vertex buffer.

SH-2791 Use request class constructor/destructor for keeping track of concurrent requests instead of unreliable increments/decrements sprinkled around the code.

SH-1427 Fix for spot lights not working properly on alpha objects, and fix for alpha lighting of point lights not matching deferred lights.

Reviewed by davep.

SH-2794 Fix for bad textures on some hardware when vbo mapping disabled (always use GL_STREAM_DRAW as the usage hint when mapping is disabled as geometry will be uploaded again and again)

SH-2598 Fix for crash when rendering mesh silhouette (workaround driver bug by rendering from client memory instead of using face VBO).