app/models/collection.rb

app/models/complaint.rb

app/models/institution.rb

app/models/learning_object.rb

app/models/review.rb

app/models/user.rb

...rate/20160512135942_add_deleted_at_to_learning_objects.rb

db/migrate/20160512140101_add_deleted_at_to_collections.rb

db/migrate/20160512140142_add_deleted_at_to_complaints.rb

db/migrate/20160512140201_add_deleted_at_to_institutions.rb

db/migrate/20160512140234_add_deleted_at_to_reviews.rb

db/migrate/20160512140321_add_deleted_at_to_users.rb