Clojure Redis client & message queue.

Macros to define an up-to-date, fully documented function for every Redis
command as specified in the official json command spec.

Handles socket connection lifecycle. Pool is implemented with Apache Commons
pool. Originally adapted from redis-clojure.

Alpha - subject to change.
Distributed lock implementation for Carmine based on work by Ronen Narkis
and Josiah Carlson. Redis 2.6+.

Redis keys:
  * carmine:lock:<lock-name> -> ttl str, lock owner's UUID.

Ref. http://goo.gl/5UalQ for implementation details.

Carmine-backed Clojure message queue. All heavy lifting by Redis.
Message circle architecture used here is simple, reliable, and has
reasonable throughput but at best mediocre latency.

Redis keys:
  * carmine:mq:<qname>:messages     - hash, {mid mcontent}.
  * carmine:mq:<qname>:locks        - hash, {mid lock-expiry-time}.
  * carmine:mq:<qname>:backoffs     - hash, {mid backoff-expiry-time}.
  * carmine:mq:<qname>:nattempts    - hash, {mid attempt-count}.
  * carmine:mq:<qname>:mid-circle   - list, rotating list of mids.
  * carmine:mq:<qname>:done         - set, awaiting gc, requeue, etc.
  * carmine:mq:<qname>:requeue      - set, for `allow-requeue?` option.
  * carmine:mq:<qname>:eoq-backoff? - ttl flag, used for queue-wide
                                      (every-worker) polling backoff.
  * carmine:mq:<qname>:ndry-runs    - int, number of times worker(s) have
                                      burnt through queue w/o work to do.

Ref. http://antirez.com/post/250 for basic implementation details

Core facilities for communicating with Redis servers using the Redis
request/response protocol, Ref. http://redis.io/topics/protocol.

Semi-automatic archival datastore layer for Carmine.
Use multiple Redis instances (recommended) or Redis databases for local key
namespacing.

Redis keys:
  * carmine:tundra:evictable - set, ks for which `ensure-ks` fail should throw

Secondary Redis server DataStore implementation for Tundra.

Simple disk-based DataStore implementation for Tundra.