BulletWorldImporter didn't properly import m_3indices16 arrays, fixes Issue 562 thanks to Marius Elvert

Support for m_3indices8 import
Fix un-initialized memPtr->m_3indices8 at export time, add a workaround at loading time

Extras/Serialize/BulletWorldImporter/btBulletWorldImporter.h

@@ -77,6 +77,8 @@ protected:
 
 	btAlignedObjectArray<int*>				m_indexArrays;
 	btAlignedObjectArray<short int*>		m_shortIndexArrays;
+	btAlignedObjectArray<unsigned char*>	m_charIndexArrays;
+
 	btAlignedObjectArray<btVector3FloatData*>	m_floatVertexArrays;
 	btAlignedObjectArray<btVector3DoubleData*>	m_doubleVertexArrays;