Added implementation for equality __eq__() and inequality __ne__() operators
Check type in __eq__() and __ne__(), simplify code
Further optimizations to CPU platform
Merge pull request #229 from peastman/master

Further optimizations to CPU platform
Major simplification to constraint handling in reference platform
Merge pull request #230 from peastman/master

Major simplification to constraint handling in reference platform
Merge pull request #227 from pgrinaway/units

Implemented equality and inequality operators for BaseDimension
Merge branch 'master' of https://github.com/SimTk/openmm