added grouped-estimator

grouped estimator got added as well as documented with pretty pictures!

patsy-addition

we added a patsy preprocessor.

second-sprint

GMMDetector and GMMClassifier got added.

first-sprint

After our first sprint with Xcellerated we got some nice features in.

1. a DebugPipline that will log helpful information
2. a RandomAdder that can add random noise on the train set but not on the test set
3. a RandomRegressor that will make somewhat random predictions meant for benchmarking
4. a pandas_utils module that has some helpers for when you're dealing with pandas