I have a small problem. What i've done so far (but not pushed yet) is:

Create a class BjyAuthorize\Service\Cache which is responsible for caching the ACL object. I also created a CacheServiceFactory which implements the FactoryInterface. Now, when i have no "cache_options" set in the module.config.php, the factory would return null. So we have to have a "default cache" in order to work with the ServiceManager. What default cache should i use? 

(If this is too hard to understand, i could set a filesystem cache as default and send another pull request, so we can discuss that.