Added parse instrumentation to print out more data in case enum renumbering failed.
Merge branch 'master' of github.com:0xdata/h2o
WIP - testing
PUB-768 - corrected response which is used for cross validation scoring.
PUB-768 fixing memory leaks

There were several memory leaks:
 - scoring results for individual validation folds were not deleted
 - scoring result for train data was not delete
 - SharedTreeModelBuilder in the context of cross validation forget to
   delete transformed response (since the builders called DRF/GBM.clone())

Minor cosmetics changes.
PUB-768 shared test for Tree Builders which tests workflow
with balance and cross-validation on binomial/multinomial
data with integer/enum response columns.

This is a generic testing strategy which individual tree builders
should override.
PUB-768 DRF tests for imbalance data with cross validation.

Minor cosmetics changes in imports.
PUB-768 GBM tests for imbalance data with cross validation
Updated all tests suite and included all tests.
PUB-768 SpeeDRF tests for imbalance data with cross validation
SpeeDRF test for balancing and cross-validation
Disable SpeeDRF tests since
 - SpeeDRF does not support handling different categoricals in
   train/test dataset
 - leaking keys
Removed abstract test from runner.
a) Updated print outs in case of an error during enum parse.
b) added few compression tests testing corner cases of C1Chunk,C1NChunk and C2Chunk
Merge branch 'master' of github.com:0xdata/h2o
Left out update from my last commit
Merge branch 'master' of https://github.com/0xdata/h2o into anqi-gbm
Remove lib/javassist for clean.
Merge branch 'master' of github.com:0xdata/h2o
Updated error prints in parse (again, to get more info in case of enum renumbering failure).