[Review] Request from 'digitaltom' @ 'SUSE/connect/review_140617_add_parameter_for_extra_payload_for_cloud_smt_registration'

Please review the following changes:
  * f28b7d6 test for instance data in payload
  * 59d5682 Merge remote-tracking branch 'origin/review_140617_fix_smt_registration_and_status_call' into review_140617_add_parameter_for_extra_payload_for_cloud_smt_registration
  * f88a64d add content of --instance-data file to announce call
  * db6b47b add --instance-data
  * 7186c55 complete test coverage
  * a84f877 Merge branch 'review_140617_fix_smt_registration_and_status_call'
  * 9984a99 require either token or url parameter
  * 6adbf90 fix --status call and test
  * 9176189 remove tests for public products
  * 0ce3f5d remove call to not existant api endpoint
--instance-data should never be sent to SCC.  Conversely if it is set, --url is also required so the data gets to SMT.
Could we add a check in here to make --instance-data without --url an error?