Summary:
Ref T603. Allows the Differential view policy to be configured with a default.
I've omitted "edit" because I want to wait and see how comment/comment-action policies work out. I could imagine locking "edit" down to only the owner at some point, and providing a wider "interact" capability, or something like that, which would cover accept/reject/commandeer. Users in this group could still edit indirectly by commandeering first.
Test Plan: Created new revisions from the CLI and conduit.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T603
Differential Revision: https://secure.phabricator.com/D7269