Merge pull request #73 from Kuang11/master

Added additional attributes to btRigidBodyConstructionInfo
make it easy to add more includes, and add btHeightfieldTerrainShape.h
disable memory init file, we prefer a single file for ammo
updated build
Added getRotation() to btMatrix3x3
Merge pull request #76 from Bunzaga/patch-2

Added getRotation() to btMatrix3x3
Many additions to ammo.idl including shapes, constraints, character controller, ghost objects, vehicle related attributes and more
Merge pull request #77 from gentooist/idl-additions

Many additions to ammo.idl including shapes, constraints, character cont...
added contactPairTest to btCollisionWorld
removed NO_DYNAMIC_EXECUTION from make.py in order to make ConcreteContactResultCallback work
added convexSweepTest and related classes to btCollisionWorld
added collision group and mask attributes to RayResultCallback and ConvexResultCallback
added btHingeConstraint
added setWorldTransform to  btCollisionObject
added btGeneric6DofConstraint and btGeneric6DofSpringConstraint
added m_closestHitFraction to ConvexResultCallback
added graphicsWorldTrans to btDefaultMotionState