Testing syntax for H2O Builders
Yank old Exec stuff, add Java Builders

Legos of M/R passes over a frame.
Fix leaking key when scoring adapting models
Try the groupby syntax, still failing generics

java generics are ... interesting....
Lower startup pause to 100ms from 1000ms
Add IcedLong & hashCode & equals
Fix bug in Exec2 ASTTable
Split new code into exec.Flow

Move "legos" into exec.Flow.
Split FlowTest into 2 files, so I can use anonymous inner classes.
Merge branch 'master' into cliffc-groupby