Fixed memory leak in btDbvtBroadphase

http://code.google.com/p/bullet/issues/detail?id=66

src/BulletCollision/BroadphaseCollision/btDbvtBroadphase.cpp

@@ -159,7 +159,11 @@ clear(m_profiling);
 //
 btDbvtBroadphase::~btDbvtBroadphase()
 {
-if(m_releasepaircache) btAlignedFree(m_paircache);
+if(m_releasepaircache) 
+{
+	m_paircache->~btOverlappingPairCache();
+	btAlignedFree(m_paircache);
+}
 }
 
 //

src/BulletCollision/BroadphaseCollision/btOverlappingPairCache.h

@@ -61,6 +61,7 @@ const int BT_NULL_PAIR=0xffffffff;
 class btOverlappingPairCache : public btOverlappingPairCallback
 {
 public:
+	virtual ~btOverlappingPairCache() {} // this is needed so we can get to the derived class destructor
 
 	virtual btBroadphasePair*	getOverlappingPairArrayPtr() = 0;