Simplify the module by removing the file includes cache table. No upgrade path, so you will need to re-install module or at least drop the module's cache table.

 - cache is no reset after a quota rule is created.

User quota is now a rule argument, allowing smart saving (i.e. save only once even if there were multiple changes).

Add rules module dependency. Module doesn't restrict content by itself - a rule created in Rules module should do it.