Remove locales with 0-5% translations.

These are not proper and just acts as clutter.
Cleanup locales for Spree 3.0.0.beta

- Remove unused keys.
- Add missing keys.
- Sort and parse syntax with Psych.
- Remove english translations in none english locales to prevent
fallback blocking.
Update translations for :sv locale now 96%
Update new :nb locale for master branch.
Merge pull request #494 from futhr/clean-locales

Clean locales for master branch.