+ Fix btSubsimplexConvexCast

Thanks to Nacho, http://www.bulletphysics.com/Bullet/phpBB3/viewtopic.php?f=9&t=2422)
Fix in rendering, GL_STENCIL
+ btTriangleIndexVertexArray indices should be unsigned int/unsigned short int,
+ Made InternalProcessAllTriangles virtual, thanks to 
Both thank to Fullmetalcoder, http://www.bulletphysics.com/Bullet/phpBB3/viewtopic.php?f=9&t=2401
+clamp impulse for btPoint2PointConstraint
Thanks to Martijn Reuvers, http://www.bulletphysics.com/Bullet/phpBB3/viewtopic.php?f=9&t=2418
+ Free memory of bvh, pass in scaling factor (optional)
Thanks to Roy Eltham, http://www.bulletphysics.com/Bullet/phpBB3/viewtopic.php?f=9&t=2375

Extras/BulletColladaConverter/ColladaConverter.cpp

@@ -1597,7 +1597,7 @@ ColladaConverter::addConcaveMesh(btCollisionShape* shape, const char* nodeName)
 		{
 			for (int t = 0; t < numFaces; t++)
 			{
-				short int* index = (short int*)indexBase;
+				unsigned short int* index = (unsigned short int*)indexBase;
 				indices.append3( index[0], index[1], index[2]);
 				indexBase += indexStride;
 			}
@@ -1605,7 +1605,7 @@ ColladaConverter::addConcaveMesh(btCollisionShape* shape, const char* nodeName)
 		{
 			for (int t = 0; t < numFaces; t++)
 			{
-				int* index = (int*)indexBase;
+				unsigned int* index = (unsigned int*)indexBase;
 				indices.append3( index[0], index[1], index[2]);
 				indexBase += indexStride;
 			}