Remove mod-only user revert system (#4178).

The mass undo system from #4178 replaces this system.

Followup to f2dccf8cf.

app/views/post_versions/index.html.erb

@@ -13,10 +13,6 @@
         <%= render "standard_listing" %>
       <% end %>
 
-      <% if params[:lr] && CurrentUser.is_moderator? %>
-        <p><%= link_to "Revert this user's changes", new_user_revert_path(:user_id => params[:lr]) %></p>
-      <% end %>
-
       <%= numbered_paginator(@post_versions) %>
     <% end %>
   </div>

app/views/static/site_map.html.erb

@@ -78,7 +78,6 @@
         <% if Danbooru.config.reportbooru_server %>
           <li><%= link_to("Top Searches", searches_explore_posts_path) %></li>
           <li><%= link_to("Missed Searches", missed_searches_explore_posts_path) %></li>
-          <li><%= link_to("Post Changes", reports_post_versions_path) %></li>
         <% end %>
       </ul>
     </section>

app/views/user_reverts/new.html.erb

@@ -1,15 +0,0 @@
-<div id="c-user-reverts">
-  <div id="a-new">
-    <h1>Revert Changes</h1>
-
-    <p>You are about to revert all changes made by <%= link_to_user @user %>. Continue?</p>
-
-    <%= form_tag(user_revert_path) do %>
-      <%= hidden_field_tag :user_id, params[:user_id] %>
-
-      <%= submit_tag "Yes" %>
-    <% end %>
-  </div>
-</div>
-
-<%= render "users/secondary_links" %>

app/views/users/_statistics.html.erb

@@ -94,9 +94,6 @@
         <th>Post Changes</th>
         <td>
           <%= presenter.post_version_count(self) %>
-          <% if CurrentUser.is_moderator? && UserRevert.can_revert?(user)%>
-            (<%= link_to "revert all", new_user_revert_path(user_id: user.id) %>)
-          <% end %>
           <% if CurrentUser.id == user.id %> 
             (<%= link_to "refresh", new_maintenance_user_count_fixes_path %>)
           <% end %>