added Samurai Monastry wavefront .obj

added alternative batching kernel (slow)
tweaked controls a bit
added command-line options --selected_demo=<int> and --new_batching
started looking into parallel 3d sap

demo/gpudemo/rigidbody/GpuConvexScene.cpp

@@ -65,7 +65,7 @@ void GpuConvexScene::setupScene(const ConstructionInfo& ci)
 				{
 					float mass = j==0? 0.f : 1.f;
 
-					btVector3 position((j&1)+i*2.2,2+j*3.,(j&1)+k*2.2);
+					btVector3 position((j&1)+i*2.2,2+j*2.,(j&1)+k*2.2);
 					btQuaternion orn(1,0,0,0);
 				
 					btVector4 color = colors[curColor];