table builder: fix various incorrect css classes.

Change calling convention to explicitly indicate whether the attributes
are for the <th> element or the <td> element. Fixes various cases where
the two were mixed up.

* Fix .col-expand classes not being set correctly on the /post_versions,
  /pool_versions, and /notes pages.

* Fix .updater and .updated-at classes not being set correctly on the
  /forum_topics page.

* Fix the name param being ignored (noticeable in the post count field
  on the /tags page).

* Don't pass empty string when column has no name.

app/views/ip_bans/index.html.erb

@@ -10,7 +10,7 @@
         <%= link_to_user ip_ban.creator %>
       <% end %>
       <% t.column :reason %>
-      <% t.column "" do |ip_ban| %>
+      <% t.column do |ip_ban| %>
         <%= link_to "Unban", ip_ban_path(ip_ban), :remote => true, :method => :delete, :data => {:confirm => "Do your really want to unban #{ip_ban.ip_addr}?"} %>
       <% end %>
     <% end %>