Should be able to manually store non-text in the memcached backend

[joshuajonah]

I am using a function that stores gzipped content in the memcached backend. The built in memcached cache.get() runs smart_unicode() on the returned text if it is detected as a string. Gzipped content is qualified as str or uncode via "if isinstance(val, basestring):", however there needs to be a way to avoid this in my case.

I've attached a simple diff in the form of an optional kwarg that works for me.

[Alex Gaynor]

Dupe of #12178.