which caused issues with negative angles
- made also UFF/AngleConstraint.cpp and MMFF/AngleConstraint.cpp more
robust against angle ranges involving negative values
- added relevant C++ and Python tests
- fixed a bug in Code/GraphMol/ForceFieldHelpers/MMFF/AtomTyper.cpp
which caused misassignment of atom types in CYGUAN01 upon shuffling
the order of atoms in the validation SDF files
- added checks for acos and asin function parameters to be within
a (-1, 1) range
to the current value) (C++/Python)
- added absolute/relative AngleConstraints (C++/Python)
- added absolute/relative TorsionConstraints (C++/Python)
- added PositionConstraints (C++/Python)
- exposed fixedPoints from Python
- added relevant C++/Python tests
- removed a number of redundant "this->" in member functions
- moved some getGrad() code into Utils::calcAngleBendGrad and
Utils::calcTorsionGrad to avoid repeating the same code
for constraints
