Show profiling information on page loads

[jvperrin]

trafficstars

It would be quite useful to show some performance information in ocfweb on page loads (to only staff when they are logged in). Khan/gae_mini_profiler might work, but I haven't tried it, I've only tried the Ruby equivalent, but it worked pretty well for Rails at least and was quite helpful for identifying performance issues on slow page loads.

[jvperrin]

@abizer suggested using jazzband/django-debug-toolbar, and it looks pretty nice.