rotation
fix TriangleConstraint for PSR invariance
add TestCase for PSR invariance.
add TriangleConstraint in python bindings.
Merge branch 'rotation' of https://github.com/Ruun/OpenANN into Ruun-rotation
Merge branch 'master' of github.com:OpenANN/OpenANN into parallel-batches

Conflicts:
	src/SigmaPi.cpp