The config was picking the wrong directory so the custom test templates
were not used during tests.

Notes

- Fix missing i18n load tags
- Remove mixed tab/space indentation
- Add two settings tests

I used the existing script [1] that cooperates very nicely with vim.
1: https://github.com/rory/django-template-i18n-lint

Fixes #676

Distinguish it from the other folders which each define a category of
test.