remove owncloud step from README, no longer needed since 398b538e2b48c3764f67d75804af65bdb8b101d2
drop the owncloud mail app for now
owncloud will only let users access it from the PRIMARY_HOSTNAME (due to its trusted_domains option being set statically), so only include /cloud in the nginx configuration for PRIMARY_HOSTNAME
make setup/owncloud.sh idempotent: don't wreck user data on second run
ownCloud: code a way to add admins from our users table, but dont use it
ownCloud: do cron the same way we do the others