Cut mirroring over to new URIs

Summary:
Ref T10748. This migrates and swaps mirroring to `PhabricatorRepositoryURI`, obsoleting `PhabricatorRepositoryMirror`.

This prevents you from editing, adding or disabling mirrors unless you know a secret URI (until the UI cuts over fully), but existing mirroring is not affected.

Test Plan:
  - Added a mirroring URI to an old repository.
  - Verified it worked with `bin/repository mirror`.
  - Migrated forward.
  - Verified it still worked with `bin/repository mirror`.
  - Wow, mirroring: https://github.com/epriestley/locktopia-mirror

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T10748

Differential Revision: https://secure.phabricator.com/D15841

src/applications/diffusion/application/PhabricatorDiffusionApplication.php

@@ -122,10 +122,6 @@ final class PhabricatorDiffusionApplication extends PhabricatorApplication {
             'testautomation/' => 'DiffusionRepositoryTestAutomationController',
           ),
           'pathtree/(?P<dblob>.*)' => 'DiffusionPathTreeController',
-          'mirror/' => array(
-            'edit/(?:(?P<id>\d+)/)?' => 'DiffusionMirrorEditController',
-            'delete/(?P<id>\d+)/' => 'DiffusionMirrorDeleteController',
-          ),
         ),
 
         // NOTE: This must come after the rule above; it just gives us a