Several large changes:

1) Changed the way that we get forms.  Now, if you want to get a form
   for a REST resource you prefix /form to the resource id.  So:
    /form/photo/1    : returns a form for editing photo id 1
    /form/comments/1 : returns a form for adding a comment to photo id 1
    /form/comment/1  : returns a form for editing comment id 1

2) Changed the comment module to have two controllers:
    comment:  deals with a single comment resource
    comments: deal with collections of comments attached to an item

Related stuff:
- Moved the comments js into the theme
- Reworked Comment_Helper for clarity
- Moved form generation code down into Comment_Helper
- Cleaned up routes (eliminating new comment ones added in recent rev)
- Added form() function to all REST controllers
- Changed comment module to use a block instead of an arbitrary helper call from the theme
- Comment controller only returns HTML currently, but returns a 201 Created status
  code when a new comment is added, which the Ajax code can catch and act upon.
- Got rid of a lot of extra views in comment module

modules/comment/views/comment.html.php

@@ -0,0 +1,11 @@
+<? defined("SYSPATH") or die("No direct script access."); ?>
+<li id="gComment-<?= $comment->id; ?>">
+  <p>
+    <a href="#" class="gAuthor"><?= $comment->author ?></a>
+    <?= comment::format_elapsed_time($comment->datetime) ?>,
+    <span class="gUnderstate"><?= strftime('%c', $comment->datetime) ?></span>
+  </p>
+  <div>
+    <?= $comment->text ?> 
+  </div>
+</li>