Use optional parameter to set column class

- Fixes the extremely long class name on the post versions view
- Can now use one value instead of having to set th and td
- Added missing column classes on all tables

app/views/bans/index.html.erb

@@ -22,7 +22,7 @@
         <%= link_to "»", bans_path(search: { banner_name: ban.banner.name }) %>
         <div><%= time_ago_in_words_tagged(ban.created_at) %></div>
       <% end %>
-      <% t.column do |ban| %>
+      <% t.column column: "control" do |ban| %>
         <% if CurrentUser.is_moderator? %>
           <%= link_to "Edit", edit_ban_path(ban) %>
           | <%= link_to "Delete", ban_path(ban), :method => :delete, :remote => true %>