Simplify trend graphs.

Update the graph output to use Date objects and parse the input
data.
Make dates go to midnight.

This is what d3 expects as well.
Add very basic regression test for new method.
Add pagination to the url view.

This will help when a page gets hit frequently.
Fix incorrect URLs

Urls weren't being handled correctly when they already had a
? in them. Fix that. Also extract twig autoloading into a function so
its easier to reuse in the test suite.
Fix pagination links being wrong.