Cache using johnny-cache + django-phased

Still need to expire the phased-cached PageDetailView.
Vary on Host header for caching
Better caching of page_detail for logged-in users.

We now use django-fancy-cache + django-phased for better caching of
the PageDetailView for logged in (appserver) hits.
Add johnny-cache dependency
Remove profiler test
https://github.com/jmoiron/johnny-cache/issues/42
Attempting to fix travis test issue w/ hostnames
Fix error w/ smart_url and cached template loader