Merge pull request #21 from needle-cookbooks/COOK-2475

COOK-2475 - Prevent celerybeat from being configured unnecessarily
Merge pull request #22 from needle-cookbooks/COOK-2484

COOK-2484: Create virtualenv and install requirements as uid/gid specified in application resource properties
Adding queues parameter to celery LWRP

Bind celery listeners to particular queues by providing an array
of queue names to the 'queues' parameter.
Merge branch 'celery_queues' into needle

* celery_queues:
  Adding queues parameter to celery LWRP