Countdown tweaks

Summary:
A few tweaks to hsb's Countdown implementation:

  - Allow the page to be rendered "chromeless", suitable for display on one of
the dozens of monitors everyone has laying around.
  - Show title of countdown in deletion dialog.
  - When creating a new countdown default to time(), not Dec 31, 1969.
  - Add extra "/" after editing to avoid needless redirect.
  - Tweak some page titles.
  - Show countdown author in list view.
  - Highlight tab in list view.
  - Tweak menu copy.
  - Link countdown title in list view, separate buttons into different columns
so they pick up padding.

Test Plan:
Created, edited and deleted a timer. Viewed a timer and toggled chrome mode.
Viewed timer list.

Reviewed By: hsb
Reviewers: hsb, aran, jungejason, tuomaspelkonen
CC: aran, hsb, epriestley
Differential Revision: 454

src/applications/countdown/controller/base/PhabricatorCountdownController.php

@@ -28,12 +28,13 @@ abstract class PhabricatorCountdownController extends PhabricatorController {
     $page->setGlyph("\xE2\x9A\xB2");
     $page->setTabs(
       array(
-        'create' => array(
+        'list' => array(
           'href' => '/countdown/',
-          'name' => 'List',
+          'name' => 'Countdown List',
         ),
       ),
       idx($data, 'tab'));
+    $page->setShowChrome(idx($data, 'chrome', true));
 
     $page->appendChild($view);