Merge branch 'release/0.80.51' into develop
More indexes to ease the admin.
Language is a foreignkey, more indexes.
version bump for 0.80.52.
Merge branch 'release/0.80.52' into develop
Merge branch 'release/0.80.52'
migration: take care of language if it exists.
version bump for 0.80.53.
Merge branch 'release/0.80.53'