Just the standard upgrade procedure applies:
* Upgrade the database with the DB upgrade tool
* Recompile your plugins and validate that no API that you used has
changed. If it has: Adapt the code, compile and deploy the new plugins.
Personal suggestion: Do this on a restored database and environment -
this way you also test your backup procedures and make sure that you
are able to restore a fully running system (before upgrade) from what
you call a backup.
