implemented rolling friction, using a contact constraint. Useful to get rolling spheres to rest, even on a slightly sloped plane.

See http://www.youtube.com/watch?v=RV7sBAsKu4M and Bullet/Demos/RollingFrictionDemo
Fixes in FractureDemo (mouse picking constraint needs to be removed, otherwise constraint solver crashes/asserts)

Demos/BasicDemo/main.cpp

@@ -18,8 +18,7 @@ subject to the following restrictions:
 #include "btBulletDynamicsCommon.h"
 #include "LinearMath/btHashMap.h"
 
-#include "GLDebugDrawer.h"
-static GLDebugDrawer sDebugDraw;
+
 
 
 	
@@ -28,7 +27,7 @@ int main(int argc,char** argv)
 
 	BasicDemo ccdDemo;
 	ccdDemo.initPhysics();
-	ccdDemo.getDynamicsWorld()->setDebugDrawer(&sDebugDraw);
+
 
 #ifdef CHECK_MEMORY_LEAKS
 	ccdDemo.exitPhysics();