20.1.0

• Bugfix: CharacterController.onGround() returns false positives after stepping (not jumping) off a cliff
• Added an IndexMesh constructor to efficiently generate visualization meshes for collision shapes; replaced DebugMeshCallback with IndexedMesh in DebugShapeFactory.
• Added 3 public methods to the IndexedMesh class:
  • copyTriangles()
  • maxDistance()
  • volumeConvex()
• Improved validation of method arguments.