Please add memcache adapter

[frops]

Often some systems have just memcache but not redis. It would be cool if you will add support memcache.

Thank you.

[NoelDavies]

Hi @frops - feel free to add a PR - but I'm pretty bogged down with work at the moment.

[gabrielfernandes-codes]

I was about to suggest actually to integrate with some PSR 6 compatible lib as Symfony Cache, where we could take advantage of all the 3 storage already in use, as make the interface to the next storage easier.