Minor refactors and additions related to connectors

Added
 - ConnectionInterface
 - Segragated options managment to the connector levels

Updated the `.travis.yml` to forward celery output to `/dev/null`
Minor refactors and additions related to connectors

Added
 - ConnectionInterface
 - Segragated options managment to the connector levels

Updated the `.travis.yml` to forward celery output to `/dev/null`
Merge branch 'enhancement/configurable-exchange-queues' into enhancement/refactor-to-ext-amqp