Update approvals in web UI to adapt to rules.pl submit_rule

The UI now shows whatever the results of the submit_rule are, which
permits the submit_rule to make an ApprovalCategory optional, or to
make a new label required. Currently making a new label required is
also going to make the change unsubmittable, as we do not yet have
a way to store the new label.

Change-Id: I9c6600c181e9f22ff980539d535caa8458d9a654
14 files changed