add quick script for starting a tmp local pipeline
be pep8 compliant
remove .progress setup

I think a better abstraction for this is to have a run_idempotent
method that makes it very clear what the tradeoffs are, rather than
trying to be magical
add p.group context manager

this can be used to reuse a cluster for multiple operations
make sure p.group cleans up after itself

and add regression test for this