Initial Python Bindings

Hi,

Hereby the initial pull request as I'm honestly not sure what else I can add to the bindings at this point.
I'll be adding more features, especially to the Python AST -> SMT/STP transformations, but in order to do that I'll probably need some actual use-cases in which I can decide what would be interesting to add. (And I don't have those at the moment - they'll probably come on a one-by-one basis by actually using the bindings.)

That being said, the bindings contain unittests for at least all *unique* functionality (i.e., there are not tests for every possible possible operator available, but most are covered, and I don't see any problems with them.)

There will probably be a need for some small changes to work with `make install` but we can start working on that now. (And I can push those changes to this very pull request while at it - before it's being merged.)

Regards,
Jurriaan

ps: There's like one extra commit modifying `INSTALL` a tiny little bit.. I guess that's ok, right? ;)