concierge-backup: update example conf

doc/examples/backup.cfg.example

@@ -5,7 +5,7 @@ BACKUP_DIR_INCL=/etc;/var/mail
 LOCAL_DIR=/var/backups
 
 # Remote backup destination
-REMOTE_ENABLE=true
+REMOTE_ENABLE=false
 REMOTE_USER=backupuser
 REMOTE_HOSTNAME=backupotron5000.example.net
 REMOTE_DIR=/var/backups
@@ -15,3 +15,4 @@ REMOTE_DIR=/var/backups
 
 # Backup encryption
 ENCRYPTION_ENABLE=false
+ENCRYPTION_PASSPHRASE_PATH=/etc/concierge/backup.passphrase