[WIP] Set up for Functional Test Suite

#### This PR

* [x] Splits the test suite into unit and functional tests organized by filesystem directories.
* [x] Adds py.test markers automatically to tests to enable categorization by unit or functional.
* [x] Creates separate tox environments for unit or functional (``pyXY-unit`` vs ``pyXY-functional``).
* [x] Adds an invoke task (``invoke generate.matrix``) to generate a new ``.travis.yml`` and ``tox.ini``.
* [x] Write a test that exercises quick order for real.
* [ ] Setup Travis (Maybe?) so that the functional tests are run on each push to master

#### Future PR
* Setup betamax so that the PRs and local testing can happen without hitting the actual API but use recorded responses.