You can clone with
Clearance cannot be added to an existing app
Since the generated migration adds non-NULL requirements to columns, and
since we never add Clearance to existing apps, we cannot trivially test
the nuances involved in that situation. For now, we do not support this.
Remove the salt from the DB migration
The salt column is only needed for SHA1 and MD5 strategies, which are
not the default. The README contains instructions for adding the salt
back before switching to those strategies.