There was some code in here to handle 'branch' operations on files already, but

it wasn't in the list of whitelisted operations, and we'd therefore error out

with "Unsupported action type "branch" for <filename>".
This change reorders the renaming of actions with the whitelist, to simplify

the list a bit and fix things.

Ran unit tests
Submitted a change involving a branched file and saw that it got posted as a

  new file.