Cleanup: removed dead code
Don't end expression prematurely
Oops, file-specific query was missing
Ensure `@get_resource` works with `Directory` objects too
Fixed an edge case and simplified code

When project and language filters choices were cleared, it was failing to
perform the redirect to the root.
Moved editor search box to action links

This also adds the new "Go back to project browser" action link in the
editor's page, which returns users to the original page they entered the
translation mode from (takes into account some contstraints).

Fixes #77 and fixes #83.