This stores a ms timestamp on the distributed cache (Jarves::setCache())
and the actual data on the high-speed cache driver (Jarves::setFastCache()).
This mechanism makes sure, you gain the maximum performance by using the
fast cache driver to store the actual data and using the distributed cache driver
to store a ms timestamp where we can check (over several jarves.cms installations)
whether the cache is still valid or not.
Use Jarves::invalidateCache($key) to invalidate this cache.
You don't have to define the full key, instead you can pass only a part of the key.