Initial UnitTest Work

Starting a pull request for some initial UnitTest and general cleanup work. Will merge into master as soon as there are some useful unit tests in place.

Also adding [Travis-CI](https://travis-ci.org/neworganizing/simple-salesforce/) integration, which should help keep pull-requests in line.

This also adds compatibility with Python 3.2 and 3.3 without relying on 2to3. That means simple-salesforce will be compatible out-of-the-box with Python 2.6, 2.7, 3.2 and 3.3.

A first step at addressing #7 (lack of UnitTests) and #20 (Python3 Support)