Log More Information About Which Split Is Being Trained

[ecsalomon]

Current logs are transparent about which splits are being tested but opaque about which ones are being trained. Add some information (e.g., start/end dates, lookback durations) about the split being trained.

2017-04-21 14:11:43,945 47821 INFO: Done with test matrix
2017-04-21 14:11:43,945 47821 INFO: Starting split
2017-04-21 14:11:43,946 47821 INFO: Checking out train matrix <-- [Train matrix info here?]
2017-04-21 14:11:43,990 47821 INFO: Checking out train labels
2017-04-21 14:11:53,110 47821 INFO: Training models```

[ecsalomon]

It also might be nice to include a simple progress line when opening a new split (e.g., Starting split 8 out of 320).

[thcrock]

Once #125 is done this will need to be updated (and we may just wait until that one is done to do this). The split may no longer be relevant, but task x out of y is definitely relevant.

[ecsalomon]

I think it might be good to log perhaps the model-matrix combo being trained in a given job. Something like:

Training sklearn.ensemble.RandomForestClassifier/{'max_depth': 20, 'criterion': 'gini', 'max_features': 'sqrt', 'n_jobs': 5, 'n_estimators': 10000} uuid on matrix uuid.

Perhaps at the debug level if this would get too spammy.