core.memoize is a memoization library offering functionality above
Clojure's core `memoize` function in the following ways:

**Pluggable memoization**

core.memoize allows for different back-end cache implmentations to
be used as appropriate without changing the memoization modus operandi.
See the `memoizer` function.

**Manipulable memoization**

Because core.memoize allows you to access a function's memoization store,
you do interesting things like clear it, modify it, and save it for later.