Use login_path instead of explicit controller and actions

This makes future refactoring easier.

app/views/browse/changeset.html.erb

@@ -64,7 +64,7 @@
 
   <% unless current_user %>
     <div class="notice">
-      <%= link_to(t(".join_discussion"), :controller => "users", :action => "login", :referer => request.fullpath) %>
+      <%= link_to(t(".join_discussion"), login_path(:referer => request.fullpath)) %>
     </div>
   <% end %>