* kmsauth will use lru-dict library for its token cache, rather than a slower pure-python implementation, if lru-dict is available.
0.5.0
* KMSTokenValidator now accepts a ``stats`` argument, which allows you to pass in an instance of a statsd client, so that the validator can track stats.
0.4.0
* KMSTokenValidator now accepts a ``token_cache_size`` argument, to set the size of the in-memory LRU token cache.