Fix up ordering issues around how we create the noderole graph.

This fixes up a couple of ordering issues around how we were initially
binding the noderole graph together that was causing weird corner cases
with the crowbar-hardware-configured and raid-configure roles.
Merge pull request #219 from VictorLowther/fix-noderole-graph-build-order

Fix up ordering issues around how we create the noderole graph.