Rough cut of repository cluster status panel

Summary:
Ref T4292. This adds some very basic cluster/device data to the new management view. Nothing interesting yet.

Also deal with disabled bindings a little more cleanly.

Test Plan: {F1214619}

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T4292

Differential Revision: https://secure.phabricator.com/D15685

src/applications/config/controller/PhabricatorConfigClusterDatabasesController.php

@@ -203,7 +203,7 @@ final class PhabricatorConfigClusterDatabasesController
           ->setIcon('fa-book')
           ->setHref($doc_href)
           ->setTag('a')
-          ->setText(pht('Database Clustering Documentation')));
+          ->setText(pht('Documentation')));
 
     return id(new PHUIObjectBoxView())
       ->setHeader($header)