Cleaned up Performance evaluation, removing files from Examples.Number and putting them in Performance. Also allows several other models, and these required some edits to model files
Merge pull request #7 from jthurst3/master

Add chi-square test, rewrite FunctionNode.__eq__
Modifications to allow Performance eval
Merge branch 'master' of https://github.com/piantado/LOTlib
fixed small bug in CombinatoryLogic
fixed small bug in CombinatoryLogic
Fixed bug in FunctionNode.__eq__ -- must check that args are FunctionNodes
other small fixes to __eq__