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
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