Kepler

This is Phase 2 for the WRM interface:
-Add a Kepler-wide provenance configuration. The intent is that the WRM interface connects to a single store no matter what workflow frame you have open - that way you are able to browse many different workflows and workflow executions at once.

This subverts the one-workflow:one-frame cardinality and also blows away the idea of having a per-workflow configuration for the provenance store.
I'm not even sure this is the direction we will ultimately take, but we need to consider it since we've mocked up some UI features that indicate a central, Kepler-wide provenance store.