added group support, however color/groupable aesthetic values lost after stats/pos xforms
made wf.block.isBarrier true.  fixes multi-layer issue
boxplot is now a groupby.  renders
groupby stats preserve originial schema + computed attrs
huge update.  modified scaleset merging, fixed scaleset.clone.  set training preserves scale aesthetics.
error messages are printed. fixed logical AND bug in set.types
fixed set.get issues with types.  try to pass table.schema.type instead of unknown
add mergedset
transforms require schemas.  fixed schema.exclude bug
fixed transform.map type testing
fixed boxplot rendering bug
merged with remote