more cloud for more test
Allow local setup/tear-down in MRTask
cleanup spacing
Remove remote data-load during Vec.toString
Cleanup UKV put/remove paths

PUT'ing over a Frame removes all included Vecs.; same for a Vec removes
all Chunks.  Code was there for remove but not an over-writing put.
Also lots of dup code removed.
Do not have DKV.put(Frame) wipe out an old Frame

Vecs are shared.  This whole model is broken, and really needs e.g.
RefCnt'ing of Vecs.
More overlap/concurrency during parse conversion

Helps auto-converter speed
Also new vec chunks don't stick around, should help with data balance.
More fabulously correct blocking on converters & slices

VA->FV and FV->VA converters and Frame.slice get properly result
blocking.
UKV.remove gets it's remove tweaked again, plus more comments.
Some debug code carefully left in Expr2Test.