make --status more robust for dispatcher, and add support for receiver

make the --status flag work by fetching a periodically recorded snapshot
of internal process state; additionally, update the callback receiver to
*also* record these statistics so we can gain more insight into any
performance issues

awx/main/dispatch/control.py

@@ -2,6 +2,9 @@ import logging
 import uuid
 import json
 
+from django.conf import settings
+import redis
+
 from awx.main.dispatch import get_local_queuename
 
 from . import pg_bus_conn
@@ -21,7 +24,9 @@ class Control(object):
         self.queuename = host or get_local_queuename()
 
     def status(self, *args, **kwargs):
-        return self.control_with_reply('status', *args, **kwargs)
+        r = redis.Redis.from_url(settings.BROKER_URL)
+        stats = r.get(f'awx_{self.service}_statistics') or b''
+        return stats.decode('utf-8')
 
     def running(self, *args, **kwargs):
         return self.control_with_reply('running', *args, **kwargs)