Add Workboard UI Color to sidenav, fix fullscreen CSS

Summary: Uses the background color changes to show also on the side nav. Places color on entire body so fullscreen doesn't show other body color.

Test Plan: Review various workboard colors at normal and fullscreen

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Differential Revision: https://secure.phabricator.com/D15283

src/applications/project/controller/PhabricatorProjectBoardViewController.php

@@ -456,7 +456,7 @@ final class PhabricatorProjectBoardViewController
       $background_color_class = "phui-workboard-{$background}";
 
       $page->addClass('phui-workboard-color');
-      $nav->addClass($background_color_class);
+      $page->addClass($background_color_class);
     }
 
     return $page;