Manage logging configuration files (feature flag)

Add a feature flag to allow this module to manage
its own log configuration files. This feature flag is
set to false currently.

Configuration files for logging come from
system-config/openstack-project. The related system-config
change is Ic5ceb7fb23a8403a31f9db2774ddd900fd838930.

Change-Id: I76851c8672968a7581622cac8ff0062c1f50e0ef

files/gearman-logging.conf

@@ -0,0 +1,33 @@
+[loggers]
+keys=root,gear
+
+[handlers]
+keys=console,normal
+
+[formatters]
+keys=simple
+
+[logger_root]
+level=WARNING
+handlers=console
+
+[logger_gear]
+level=DEBUG
+handlers=normal
+qualname=gear
+
+[handler_console]
+level=WARNING
+class=StreamHandler
+formatter=simple
+args=(sys.stdout,)
+
+[handler_normal]
+level=WARNING
+class=logging.handlers.WatchedFileHandler
+formatter=simple
+args=('/var/log/zuul/gearman-server.log',)
+
+[formatter_simple]
+format=%(asctime)s %(levelname)s %(name)s: %(message)s
+datefmt=