Bugfix/null translation
Created by: mira13
#478 Description
Bugfix, that makes canonical_translation_id NULL on translation delete
Use case
When translation is removed, links to the translation still thers in transcript table
Benefits
Data consistency for translation table
Possible Drawbacks
Not found
Testing
Unit tests are added for this case
If so, do the tests pass/fail?
All tests pass, with travis as well