Started documenting and improving the exceptions
Merge from master
Added a heteroCollectionException to Exceptions.py
Implemented the visit_* to get while loops working. This meant visit_while, visit_compare, and a few other. I added a bool class to the NameSpaceBean builder and one fun def.
Merge pull request #47 from daviis/visitLoadStore

Improved exception docs and hierarchy
Merge pull request #48 from daviis/visitWhile

Visit while
Had to manually merge though I didn't see the issues. You might want to check over what you added and make sure it's right, I think it is but I'm not sure?