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/post_events/index.html.erb

@@ -3,7 +3,7 @@
     <h1>Post Events</h1>
 
     <%= table_for @events, class: "striped autofit", width: "100%" do |t| %>
-      <% t.column :type_name, nil, { name: "Type" } %>
+      <% t.column :type_name, name: "Type" %>
       <% t.column "User" do |event| %>
         <% if event.is_creator_visible? %>
           <%= link_to_user event.creator %>
@@ -12,12 +12,12 @@
         <% end %>
         <br><%= time_ago_in_words_tagged event.created_at %>
       <% end %>
-      <% t.column "Description", {}, { class: "col-expand" } do |event| %>
+      <% t.column "Description", td: { class: "col-expand" } do |event| %>
         <div class="prose">
           <%= format_text event.reason %>
         </div>
       <% end %>
-      <% t.column :is_resolved, {}, name: "Resolved" %>
+      <% t.column :is_resolved, name: "Resolved" %>
     <% end %>
   </div>
 </div>