TODO

code cleanup, isolate core to move between redis and zmq
protocols:
    sqs endpoint
    memcached endpoint
    nats endpoint
job scheduling with mure


engine.py:    - TODO: the object may have an expiration instead of straight deletion
engine.py:    - TODO: RPOPLPUSH can be used to put it in another queue as a backlog
engine.py:    - TODO: persistence management (on/off/status)
engine.py:                if uuid == 1: # TODO: use ismember()
engine.py:        # TODO: how to implement get reference counting ? is it necessary (redis opers are atomic...) 
engine.py:        # TODO: cleanup in delete

build a presence service (or use XMPP stuff) to sync more than 1 server doing comet.