Use oslo_log instead of logging

1. the use of the log in the module should be unified.
2. oslo_log wrapped logging.

Change-Id: Iac48fcbcd2fc9a7002fed6a328dc74242ad770de

watcher/common/service.py

@@ -15,7 +15,6 @@
 # under the License.
 
 import datetime
-import logging
 import socket
 
 from oslo_concurrency import processutils
@@ -332,7 +331,7 @@ def prepare_service(argv=(), conf=cfg.CONF):
     cfg.set_defaults(_options.log_opts,
                      default_log_levels=_DEFAULT_LOG_LEVELS)
     log.setup(conf, 'python-watcher')
-    conf.log_opt_values(LOG, logging.DEBUG)
+    conf.log_opt_values(LOG, log.DEBUG)
     objects.register_all()
 
     gmr.TextGuruMeditation.register_section(_('Plugins'), opts.show_plugins)