Added hdp2.0.6
Added build for hdp2.0.6.
Merge branch 'master' into tomk-hadoop
Start of real key locking
Next step of real locking ...
Real locking starts to work for GBM, DRF2, GLM1, GLM2

Lockable.update takes the Job key doing the update.
SharedTreeBuilder locks & unlocks the input datasets.
DGLM locks & unlocks the xval models.
More locking work

GLM1 read-locks input datasets
Pass Futures thru Lockable.delete
doc for str
str test
Locking fixes for lots of algos

KMeans, KMeans2, RF1, a bunch of RF tests
Exec2 is a work-in-progress still
Merge branch 'master' of https://github.com/0xdata/h2o
Actually Lock and Unlock, plus global Key gather

Lock collisions still cause death tho
TaskSendKey to "push" a Key to some other node.  Used to gather keys
across the cluster for a global view.
Rename H2O.keySet to H2O.localKeySet.
Add H2O.globalKeySet
Value.backend() vs _persist&BACKEND
Fixed glmva validation for multi-chunk datasets. Reduce had misspelling causing it to ignore the other chunk results.
Merge branch 'master' of github.com:0xdata/h2o
Another UKV remove for RF1
Merge branch 'master' of https://github.com/0xdata/h2o
did stuff to doc gen
moved filtering of constant columns in glmva one layer in so it can not be avoided by caller.
Merge branch 'master' of github.com:0xdata/h2o
Merge branch 'master' into tomk-hadoop