Share rendering code for embedded votes and vote detail

Summary:
We have two separate pieces of rendering code and both are pretty ugly. Move them toward being more reasonable.

This could no doubt be improved:

  - Getting a text style which was readable on both the dark and light bars was hard, maybe we should change the colors or maybe I am just bad.
  - Could probably benefit from actual competent design in general.
  - JS magic is temporarily ineffective, I'll restore that in the future.
  - Embed style is a little funky (margin/centering).
  - Could use a little cleanup.

Test Plan:
{F50226}
{F50227}
{F50228}

Reviewers: chad, btrahan

Reviewed By: btrahan

CC: aran

Differential Revision: https://secure.phabricator.com/D6465

src/applications/slowvote/controller/PhabricatorSlowvoteEditController.php

@@ -51,7 +51,7 @@ final class PhabricatorSlowvoteEditController
     if ($request->isFormPost()) {
       $v_question = $request->getStr('question');
       $v_description = $request->getStr('description');
-      $v_responses = $request->getInt('responses');
+      $v_responses = (int)$request->getInt('responses');
       $v_shuffle = (int)$request->getBool('shuffle');
 
       if ($is_new) {