move default log setup to _log_default from init_logging

allows classes to be passed log attribute, avoiding duplicate setup and occasional errors if things are done in the wrong order.

IPython/frontend/html/notebook/clustermanager.py

@@ -45,8 +45,6 @@ class DummyIPClusterStart(IPClusterStart):
 
     def init_signal(self):
         pass
-    def init_logging(self):
-        pass
     def reinit_logging(self):
         pass
 

IPython/frontend/html/notebook/notebookapp.py

@@ -390,7 +390,6 @@ class NotebookApp(BaseIPythonApplication):
         self.cluster_manager.update_profiles()
 
     def init_logging(self):
-        super(NotebookApp, self).init_logging()
         # This prevents double log messages because tornado use a root logger that
         # self.log is a child of. The logging module dipatches log messages to a log
         # and all of its ancenstors until propagate is set to False.
@@ -493,6 +492,7 @@ class NotebookApp(BaseIPythonApplication):
     
     @catch_config_error
     def initialize(self, argv=None):
+        self.init_logging()
         super(NotebookApp, self).initialize(argv)
         self.init_configurables()
         self.init_webapp()