[Review] Request from 'digitaltom' @ 'SUSE/connect/review_140711_add_support_for_updating_hardware_info'

Please review the following changes:
  * c3aaeec update system automatically on product activations
  * 669ed04 add update_system() to the yast layer
  * ef225be test for Clinet.update_system()
  * 6556c15 renamed basic_auth to system_auth
  * bf7b985 add update_system method to api class