Use attribute relations & API when updating Attribs

This code brings the UI up to date with the new Attrib hotness.
DeploymentRole and NodeRole raw/default views now use the Attrib lists for rendering and API for update
Both use the same partial for render.

TO DO:
* catch and return errors from the API (we need a generic pattern for this)
* allow barclamps to override the default render in a useful way

Minor other cleanups included in this pull.

Related to CES-1599