This Memory adapter provides basic support for `write`, `read`, `delete`
and `clear` cache functionality, as well as allowing the first four
methods to be filtered as per the Lithium filtering system.

This cache adapter does not implement any expiry-based cache invalidation
logic, as the cached data will only persist for the lifetime of the current request.

As a result, this cache adapter is best suited for generic memoization of data, and
should not be used for for anything that must persist longer than the current
request cycle.