Switch to the new centralized templates for admin form pages.
Review Request #7852 — Created Jan. 7, 2016 and submitted — Latest diff uploaded
Djblets has a new set of common admin form templates meant to replace the usage of the siteconfig-hosted templates. This doesn't impact Review Board much, but we do make use of some now-deprecated templates. This switches over to using the new ones where appropriate.
Tested each of the affected pages.