/*
Package writebehind provides a cache that periodically syncs to a datastore.

The Cache is really only useful for adding numbers that are expected to change
too frequently for a full datastore write, e.g. view counts.

Each Cache can only be used once; calling its Stop() method renders the Cache
unusable, and a new Cache needs to be instantiated. Caches should, wherever
possible, have their Stop() methods called, or they risk leaking goroutines.

Cache implements the expvar.Var type, and instances can be passed to
expvar.Publish to provide insight into the Cache while it's in operation.
*/
package writebehind