pluggable cache system

[pjpritch]

caching subsystems are great, and having the ability to use an in-memory cache, file cache, Memcached, Redis-cached, etc ... is always nice

[pjpritch]

in all cases, the interface would be the same XXX.get('path') XXX.set(path, object), where maybe the third arg is options (which might include expiration date/TTL)