Texture is now set to 0(NULL) INSIDE of the mutex lock when freeing it in BTHResourceManager.cpp.

Signed-off-by: Markus Tillman <reetopps6@hotmail.com>
Merge branch 'master' of https://github.com/Malow/NDYGFX

Conflicts:
	ModelViewer/Source/TestRealisticScene.h

Signed-off-by: Markus Tillman <reetopps6@hotmail.com>