add ability to delete posts

views/threads/post.etlua

@@ -53,7 +53,13 @@
           local reply_text = ("%s\n[quote]%s[/quote]\n---\n\n"):format(quote_src_text, post.original_markup)
         %>
           <button value="<%= reply_text %>" class="reply-button">Reply</button>
-        <% end %>
+      <% end %>
+      <%
+        local show_delete = (post.user_id == me.id and not ntob(thread.is_locked)) or me:is_mod()
+        if show_delete then
+      %>
+          <button class="critical post-delete-button" value="<%= post.id %>">Delete</button>
+      <% end %>
       </span>
     </div>
     <div class="post-content">