booleanOperations

Merge pull request #25 from anthrotype/staticmethod

[booleanOperations] version 0.3

[booleanOperations.__init__] export BooleanOperationManager static methods as module-level functions for easier import

[booleanOperationManager] use @staticmethod for BooleanOperationManager methods and make _performOperation a module-level function

[setup.py] use sys.exit() instead of exit()