Now tuning parameters based upon graph predictions.
(1) add intercept back to cost model, it does improve things
(2) code for generating graphs 16-20

TODO
- bring tests back up to date
- some of the unit tests are integration tests and should be run by failsafe
- repackage the tests to match the code packaging
(1) moved python code into a better spot
(2) repurposed a coursera homework assignment for generating all pairs shortest paths in the predicted graphs