Allow the Default/Backlog column to be renamed

Summary: Fixes T5101. There's no technical reason not to allow this, it just took a little extra work so I didn't do it originally.

Test Plan: Renamed "Backlog", un-renamed it. Tried to hide it.

Reviewers: chad

Reviewed By: chad

Subscribers: epriestley

Maniphest Tasks: T5101

Differential Revision: https://secure.phabricator.com/D9721

src/applications/project/controller/PhabricatorProjectBoardViewController.php

@@ -175,9 +175,7 @@ final class PhabricatorProjectBoardViewController
         ->setHeader($column->getDisplayName())
         ->setHeaderColor($column->getHeaderColor());
 
-      if (!$column->isDefaultColumn()) {
-        $panel->setEditURI($board_uri.'column/'.$column->getID().'/');
-      }
+      $panel->setEditURI($board_uri.'column/'.$column->getID().'/');
 
       $panel->setHeaderAction(id(new PHUIIconView())
         ->setIconFont('fa-plus')