Fix of broken link in DRF1.

Link to a tree viewer contained unused parameter.
Merge branch 'master' of github.com:0xdata/h2o
Merge branch 'master' of github.com:0xdata/h2o
exec2: remove / from legal id letters.
scala stub doc
Merge branch 'master' of https://github.com/0xdata/h2o
Updated documentation for HTWO-3 and fixed mean function
Merge branch 'master' of https://github.com/0xdata/h2o
k-means NaN when cluster is not assigned any row: HEX-1249, HEX-1501
exec2 adds R like && and ||
Merge branch 'master' of github.com:0xdata/h2o
Fix for HEX-1440: bad response variable selection

If response column was not selected, RFView was guessing wrong column.
Merge branch 'master' of github.com:0xdata/h2o
GLM2 bug fix and code cleanup: Local glm object model kept in GLM2 while computing glm iterations was not being updated with the most recent version from DKV leading to losing some validation.

Also, returned separate progress views and removed some obsolete/duplicate methods.
Tiny update in RPC. When checking for remote exception, call getDException instead of (fork join method) getException.
Merge branch 'master' of github.com:0xdata/h2o
exec2: added seq_len
Merge branch 'master' of github.com:0xdata/h2o
Fix for HEX-1486. Added auto-shutdown of H2O on http://127.0.0.1:54321 when user quits R session.
Merge branch 'master' of https://github.com/0xdata/h2o