Make 'CP::RemoteDevice#update should update BOOTID' spec pass.
Change spec '...should update expiration date' to use #change instead of
2 expectations for test before and after.
* lib/rupnp/cp/remote_device.rb:
  Correct a bug on handling CONFIGID: RemoteDevice did not handle CONFIGID on
  first notification, but only on updates.

* spec/cp/remote_device_spec.rb:
  Make '#update should update CONFIGID.UPNP.ORG' spec pass.