Prepare to stop inserting NotificationHistory at the time of inserting a notificaiton.

Need to remove foreign key to complaints.
Make sure if getting Notification.id we look to both tables.

migrations/versions/0293_drop_complaint_fk.py

@@ -0,0 +1,21 @@
+"""
+
+Revision ID: 0293_drop_complaint_fk
+Revises: 0292_give_users_folder_perms
+Create Date: 2019-05-16 14:05:18.104274
+
+"""
+from alembic import op
+
+
+revision = '0293_drop_complaint_fk'
+down_revision = '0292_give_users_folder_perms'
+
+
+def upgrade():
+    op.drop_constraint('complaints_notification_id_fkey', table_name='complaints', type_='foreignkey')
+
+
+def downgrade():
+    op.create_foreign_key('complaints_notification_id_fkey', 'complaints',
+                          'notification_history', ['notification_id'], ['id'])