Hello. I can't edit the categories for this plugin because the box isn't showing on the dashboard as described in the readme.txt file. I've read somewhere this may be because of a conflict with this plugin and another. My question is, where are the categories stored? Are they as folders in the file system, or a mysql table? I ask because rather than troubleshooting further it may just be easier for me to edit the categories manually, for example through phpmyadmin if they're in the mysql database, but I can't seem to see them there. How and where are the categories stored?