Big cleanup of water directory.
Move common model-building logic to hex.
Move cluster-health logic to water/init.
Merge branch 'master' into cliffc-cleanup

Conflicts:
	h2o-algos/src/main/java/hex/deeplearning/DeepLearningModel.java
	h2o-core/src/main/java/water/api/ModelParametersSchema.java
More debug printout
Convert Frame to Key<Frame>
Prevents making endles copies of Frames
Merge branch 'master' into cliffc-cleanup
Merge branch 'master' of github.com:0xdata/h2o-dev