PUB-784: Resolve merge conflicts, WIP toward sparsity constraints.
Merge branch 'arno-deeplearning2' of https://github.com/0xdata/h2o into arno-deeplearning2
PUB-603: Working example of bias-driven sparse auto-encoder.
Merge branch 'master' into arno-deeplearning2

Conflicts:
	src/test/java/water/JUnitRunnerDebug.java
Turn off logging to KV when we get an network error

ELse we get another network error during the log-to-KV, and recurisively
try to log it
Merge branch 'master' of github.com:0xdata/h2o
Merge branch 'master' of github.com:0xdata/h2o
Merge branch 'tomas_glm'
typo import_files
get rid of one rf dataset that needs to be regression
Merge branch 'master' of github.com:0xdata/h2o
Reject a job without specified response.
Fix of NPE reported yesterday by Sri.

If grid search was specified but required response was not selected,
then job call (DRF/GBM/DL/...) failed on NPE.
The problem was that required
parameters were not checked in grid search control path.
Error recovery fix:

1) added back assert that task is computed when ackack is received and task is about to be removed  (added second flag to distinguish computed and computedAndReplied states).

2) fixed another potential double auto buffer close path in RPC.call.

3) changed the way exception is set to DTask, there were two places in the code with different way how to set exception to task, unified both to run  inside synchronized(RPC) and do nothing is exception is already set.
Merge branch 'master' of github.com:0xdata/h2o
Removed onCompletion from DTask(was causing issues with multiple setException invocations).

DTask.setException should only be set by RPC (if it is remote call), local exception should be handled by standard fork join error propagation.
stash response.min() in the model.
move model refs in the exec_impl into the buildForest() call
Fix SpeeDRF model locking.
Fix possible NPE.
fix a few leaky keys
Fix NPE in Cancel found by test:
test_rf_1ktrees_job_cancel_fvec/Basic/test_rf_1ktrees_job_cancel_fvec/