Manage Upload Types is a WordPress plugin that makes it easy to change the 
file types allowed to be uploaded to media library. 

TODO
====
* Dynamically update the displayed table when a type is added rather than
calling document.reload(). 
* Do at least some rudimentary validation on the file extension and 
mimetype when they are added. 
* Check that the file extension doesn't already exist when it is added
and fail if it does. (User can remove and add to change an extension's 
mimetype.)
* Report failures rather than failing silently. 
* What happens if both "txt" and "txt|text" exist as extensions? 
