replace celery task decorators with a kombu-based publisher

this commit implements the bulk of `awx-manage run_dispatcher`, a new
command that binds to RabbitMQ via kombu and balances messages across
a pool of workers that are similar to celeryd workers in spirit.
Specifically, this includes:

- a new decorator, `awx.main.dispatch.task`, which can be used to
  decorate functions or classes so that they can be designated as
  "Tasks"
- support for fanout/broadcast tasks (at this point in time, only
  `conf.Setting` memcached flushes use this functionality)
- support for job reaping
- support for success/failure hooks for job runs (i.e.,
  `handle_work_success` and `handle_work_error`)
- support for auto scaling worker pool that scale processes up and down
  on demand
- minimal support for RPC, such as status checks and pool recycle/reload

awx/settings/development.py

@@ -68,13 +68,6 @@ template['OPTIONS']['loaders'] = (
     'django.template.loaders.app_directories.Loader',
 )
 
-# Disable capturing all SQL queries when running celeryd in development.
-if 'celery' in sys.argv:
-    SQL_DEBUG = False
-
-CELERYD_HIJACK_ROOT_LOGGER = False
-CELERYD_LOG_COLOR = True
-
 CALLBACK_QUEUE = "callback_tasks"
 
 # Enable dynamically pulling roles from a requirement.yml file
@@ -149,15 +142,6 @@ except ImportError:
 
 CLUSTER_HOST_ID = socket.gethostname()
 
-# Supervisor service name dictionary used for programatic restart
-SERVICE_NAME_DICT = {
-    "celery": "celery",
-    "callback": "receiver",
-    "runworker": "channels",
-    "uwsgi": "uwsgi",
-    "daphne": "daphne",
-    "nginx": "nginx"}
-
 try:
     socket.gethostbyname('docker.for.mac.host.internal')
     os.environ['SDB_NOTIFY_HOST'] = 'docker.for.mac.host.internal'