Added the logic but encountered some errors we can talk about at a meeting
Also fixed the walker using hasMethod instead of hasFun in the visit_BinOp
Fixed a few things and added some debug messages to look at during the meeting
Made visit_unop return a str rep of a type not a str of the operand
Merge pull request #45 from daviis/visitLoadStore

Visit load store / exception framework
Merged in master
Turns out there's only 3 unary ops, +, - and ~. Absolute value was actually a call. I looked into adding an exception for unary ops instead of only binary ops for missing magic methods but couldn't get the adding default values to parameters to work. Added a pair of items to the namespace for int, __pos__ and __neg__
Started documenting and improving the exceptions
Merge pull request #46 from daviis/UnOpLogic

Looks good to me. We can expand the namespace later, its still functional for now. Abs is going to be one of the builtin funs, like print.
Merge from master