Remove the DjDT profiling panel from devstack.py. It appears to cause…

Remove the DjDT profiling panel from devstack.py. It appears to cause horrendeous performance issues, while offering very little benefit.

lms/envs/devstack.py

@@ -62,7 +62,10 @@ DEBUG_TOOLBAR_PANELS = (
     'debug_toolbar.panels.signals.SignalsPanel',
     'debug_toolbar.panels.logging.LoggingPanel',
     'debug_toolbar_mongo.panel.MongoDebugPanel',
-    'debug_toolbar.panels.profiling.ProfilingPanel',
+    # ProfilingPanel has been intentionally removed for default devstack.py
+    # runtimes for performance reasons. If you wish to re-enable it in your
+    # local development environment, please create a new settings file
+    # that imports and extends devstack.py.
 )
 
 DEBUG_TOOLBAR_CONFIG = {