Don't check epoch boundary in MetadataAttribute.setExpiryDate

attributes.go

@@ -190,9 +190,6 @@ func (attr *MetadataAttribute) setValidityDuration(weeks int) {
 
 func (attr *MetadataAttribute) setExpiryDate(timestamp *Timestamp) error {
 	expiry := time.Time(*timestamp).Unix()
-	if expiry%ExpiryFactor != 0 {
-		return errors.New("Expiry date does not match an epoch boundary")
-	}
 	signing := attr.SigningDate().Unix()
 	attr.setValidityDuration(int((expiry - signing) / ExpiryFactor))
 	return nil