Updates cache methods

* Adds support for complex queries with multiple parameter parts
(tested ok)

* Adds ability to pass expires_in to acts_as_cached (tested ok)

* Adds adherence to Rails's global action_controller.perform_caching
setting (ok - no change)

* Adds ability to use cache namespacing

* Supports master / slave database read / write splitting, where
resetting the cache reads from the database master for both Makara and
DbCharmer (makara tested, dbcharmer - no change)