Required files
cancan/ability
cancan/rule
cancan/controller_resource
cancan/controller_additions
cancan/model_additions
cancan/exceptions
cancan/inherited_resource
cancan/model_adapters/abstract_adapter
cancan/model_adapters/default_adapter
cancan/model_adapters/active_record_adapter
cancan/model_adapters/data_mapper_adapter
cancan/model_adapters/mongoid_adapter