Signconf with no keys

I had a policy which the enforcer did not like, thus not inserting the key in the zone. It will however create the signconf, which now contains no keys. The signer does not like this as it is not following the XML schema. The enforcer should check if there are any keys before writing the signconf or we should adjust the XML schema.

Jun 4 11:18:24 ubuntu ods-enforcerd: [enforcer] updatePolicy Key lifetime unreasonably short with respect to TTL. Will not insert key!

/var/opendnssec/signconf/bellgrim.se.xml:18: element Keys: Relax-NG validity error : Expecting an element , got nothing