Bug fixes for AMQP connected and Redis pub/sub

- implements redis pub/sub for task results
- fixed problems with AMQP due to library changes
- updated readme
pinned celery version cleaned an errant echo from mongo
 updates to fix unit tests effected by timing of service initations
Merge branch '3.1' into exp/test

Conflicts:
	.travis.yml
	library/Rhubarb/ResultStore/Mongo.php
Refactor for uniformity of connection string option

All connections now expect the connection string defined as
`connection`, while `uri` will continue to function it is officially
deprecated in its use.