Fix for extra logging output by default by supervisorctl

- This adds a loglevel setting for supervisorctl patterned after the
  supervisord loglevel, and it defaults to warn instead of info so that
  it doesn't log the files that are included by default as that's a very
  breaking behavior for anything using the supervisorctl output.

supervisor/options.py

@@ -1673,6 +1673,7 @@ def __init__(self):
         self.configroot.supervisorctl.username = None
         self.configroot.supervisorctl.password = None
         self.configroot.supervisorctl.history_file = None
+        self.configroot.supervisorctl.loglevel = 'warn'
 
         from supervisor.supervisorctl import DefaultControllerPlugin
         default_factory = ('default', DefaultControllerPlugin, {})
@@ -1688,14 +1689,16 @@ def __init__(self):
         self.add("username", "supervisorctl.username", "u:", "username=")
         self.add("password", "supervisorctl.password", "p:", "password=")
         self.add("history", "supervisorctl.history_file", "r:", "history_file=")
+        self.add("loglevel", "supervisorct.loglevel", "e:", "loglevel=",
+                 logging_level, default="warn")
 
     def realize(self, *arg, **kw):
         Options.realize(self, *arg, **kw)
         if not self.args:
             self.interactive = 1
 
         format = '%(levelname)s: %(message)s\n'
-        logger = loggers.getLogger()
+        logger = loggers.getLogger(self.loglevel)
         loggers.handle_stdout(logger, format)
         self._log_parsing_messages(logger)
 
@@ -1750,6 +1753,8 @@ def read_config(self, fp):
             section.history_file = None
             self.history_file = None
 
+        section.loglevel = logging_level(parser.getdefault('loglevel', section.loglevel))
+
         self.plugin_factories += self.get_plugins(
             parser,
             'supervisor.ctl_factory',