In #177 we found that tosca.nodes.Database TOSCA normative type has
a port property which is described to be optional but its type
definition doesn't explicitly set required keyname to false, so we had
to do it in order to prevent that opera would treat it as a required
TOSCA property which would be against the TOSCA standard.
In #177 we found that tosca.nodes.Database TOSCA normative type has a port property which is described to be optional but its type definition doesn't explicitly set required keyname to false, so we had to do it in order to prevent that opera would treat it as a required TOSCA property which would be against the TOSCA standard.
Fixes #177.