Make atom and ring hybridization filters consistent

[jthorton]

    Thanks, @jthorton , this looks good to me! 
    I just have one general question to this filter:
    Right now, this only removes / disallows mappings between an aromatic and aliphatic ring. 
    Would we also want to disallow mapping e.g. two aliphatic rings with different hybridization of some atoms (e.g. 
    cyclohexane and cyclohexene) or should those cases be handled in the atom hybridization change filter?

Originally posted by @hannahbaumann in #65 (review)