How to upgrade owncloud

I deployed a turnkeylinux appliance with owncloud builtin.  Owncloud version 12.1  I see turnkey now has a owncloud version 13.0  How would I go about upgrading without uploading new source that I downloaded from owncloud.  Is there a way to upgrade.  It doesnt want to seem to get the new version through webmin.

Thanks,

Stan