Pools + Logged out options + Undefined begone

Including the changes from 2.4:
* The "undefined" error should be fixed.
* Logged out users now have access to the resize and similar options in the sidebar.
* Pools are now supported, but this feature will probably be slower for some since it has to use two API requests to get the information needed. When Danbooru is slow, this will definitely be noticeable.
* I've added in the update meta tags so I assume that will allow the script to update automatically.

By all means, give this a test run (specifically in the pools section) before officially releasing it. I haven't managed to run into any problems... yet.