Add an id xml attribute to resource-adpter containing DMR resource name

<xs:attribute name="id" type="xs:token" use="optional"><xs:annotation><xs:documentation>[
An unique identifier for the resource adapter
</xs:documentation></xs:annotation></xs:attribute>

In case it is null resource name in DMR have to be generated (as now) and marshall in this attribute.
This way also generated name will be consistent after a server reload