Configure rsyslog to listen over a unix domain socket instead of a port

- Add a placeholder rsyslog.conf so it doesn't fail on start
 - Create access restricted directory for unix socket to be created in
 - Create RSyslogHandler to exit early when logging socket doesn't exist
 - Write updated logging settings when dispatcher comes up and restart rsyslog so they  take effect
 - Move rsyslogd to the web container and create rpc supervisor.sock
 - Add env var for supervisor.conf path

awx/settings/defaults.py

@@ -955,6 +955,7 @@ CHANNEL_LAYERS = {
 }
 
 # Logging configuration.
+LOGGING_SOCK = '/var/run/tower/sockets/rsyslog.sock'
 LOGGING = {
     'version': 1,
     'disable_existing_loggers': False,
@@ -1011,9 +1012,9 @@ LOGGING = {
             'formatter': 'simple',
         },
         'external_logger': {
-            'class': 'logging.handlers.SysLogHandler',
+            'class': 'awx.main.utils.handlers.RSysLogHandler',
             'formatter': 'json',
-            'address': ('localhost', 51414),
+            'address': LOGGING_SOCK,
             'filters': ['external_log_enabled', 'dynamic_level_filter'],
         },
         'tower_warnings': {