Bugfix: revert concave early out, see https://github.com/bulletphysics/bullet3/issues/4263
Another fix from 3.24: avoid memory buildup when using createMultiBody, thanks to Jason Peng for the report and reproduction case. Minor fix, related to issue with debug line drawing, introduced in addUserDebugPoints patch. Also, remove C++11 'override'.
For further changes see the commit history....
