IsomorphismMolAtomMapper
Fitting molecules by isomorphism
IsomorphsimMolAtomMather
unit test for MoleculeMatcher
add more molecules
add test for group_molecules, to_dict, from_dict
Merge branch 'master' of github.com:xhqu1981/pymatgen

Conflicts:
	pymatgen/analysis/molecule_matcher.py
test files for MoleculeMatcher