- added quickSort to btAlignedObjectArray (has generally better performance then heapSort)

- replaced all usage of heapSort by quickSort
- finished btMultiSapBroadphase. Still some work to be done to increase performance (faster add/remove from child broadphases. 
  uses currently AABB tree to locate child broadphase (should use grid), and sorted array takes too much time.

src/LinearMath/btAlignedObjectArray.h

@@ -253,6 +253,46 @@ class btAlignedObjectArray
 				}
 		};
 	
+		template <typename L>
+		void quickSortInternal(L CompareFunc,int lo, int hi)
+		{
+		//  lo is the lower index, hi is the upper index
+		//  of the region of array a that is to be sorted
+			int i=lo, j=hi;
+			T x=m_data[(lo+hi)/2];
+
+			//  partition
+			do
+			{    
+				while (CompareFunc(m_data[i],x)) 
+					i++; 
+				while (CompareFunc(x,m_data[j])) 
+					j--;
+				if (i<=j)
+				{
+					swap(i,j);
+					i++; j--;
+				}
+			} while (i<=j);
+
+			//  recursion
+			if (lo<j) 
+				quickSortInternal( CompareFunc, lo, j);
+			if (i<hi) 
+				quickSortInternal( CompareFunc, i, hi);
+		}
+
+
+		template <typename L>
+		void quickSort(L CompareFunc)
+		{
+			//don't sort 0 or 1 elements
+			if (size()>1)
+			{
+				quickSortInternal(CompareFunc,0,size()-1);
+			}
+		}
+
 
 		///heap sort from http://www.csse.monash.edu.au/~lloyd/tildeAlgDS/Sort/Heap/
 		template <typename L>