OO interface for menu rules matching. Removed eval.
removed useless sys.path hack in test case
use ast module for menu rule matching
we don't "do" rules, we "apply" them...
added Rule factory methods
fixed issue with python3.3 error when BoolOp has only one value
support & tests for empty Rules
refactored Rule parsing methods out of the Rule class
Merge pull request #3 from ju1ius/rules-ast

Used ast module to compile menu rules matching code