Improve translations api with detecting languages

[nickvergessen]

Summary

1. Fix a bug that when the first translation provider was unable to detect a language translations would not work
2. Return the from language (on success and error) so that clients can select the proper option and/or give hints to the user how they can get closer to a translation

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)