Cache wildcards - Find / delete all cache starting with prefix

I'm a cache noob so will rely on others' expertise, but these methods seem appealing assuming they can be handled in all drivers and done efficiently.

Thanks for the reply! I think this might interest some people. Also, I did some research and found that it could be done easily in the majority of handlers. Memcached will be the painful one apparently! I'll work on a PR in the coming days.