First cut of #54: ThymeLeaf => FreeMarker

We're closer to "bare-metal" HTML. Some pages are broken (search,
notably); suggestion page still works!
Part of #54: reinstated search form in header. Sort of.
Part of #54: All browser pages are now in FreeMarker.
Resolved #54: complete transition to FreeMarker

- Revert suggestion page URL
- Fix search
- Update tests to poke model for data
- Reinstate upload view