btMultiBodyConstraintSolver writes back the applied impulse for contact points

(added some debugging output for this in the demos, commented-out by default)

Demos3/bullet2/FeatherstoneMultiBodyDemo/MultiDofDemo.cpp

@@ -46,6 +46,25 @@ void	MultiDofDemo::stepSimulation(float deltaTime)
 	float internalTimeStep = 1./240.f;
 	m_dynamicsWorld->stepSimulation(deltaTime,10,internalTimeStep);
 //		CProfileManager::dumpAll();
+	/*
+	for (int i=0;i<m_dynamicsWorld->getDispatcher()->getNumManifolds();i++)
+	{
+		btPersistentManifold* contact = m_dynamicsWorld->getDispatcher()->getManifoldByIndexInternal(i);
+		for (int c=0;c<contact->getNumContacts();c++)
+		{
+			btManifoldPoint& pt = contact->getContactPoint(c);
+			btScalar dist = pt.getDistance();
+			if (dist< contact->getContactProcessingThreshold())
+			{
+				printf("normalImpulse[%d.%d] = %f\n",i,c,pt.m_appliedImpulse);
+				
+			} else
+			{
+				printf("?\n");
+			}
+		}
+	}
+	*/
 }