MBS-5726, implement /ws/2/discid for json webservice.
MBS-5726, add /ws/2/discid json test.
MBS-5726, render /ws/2 included discids as "discs" instead of "discids", to be consistent with the XML webservice.
MBS-5726, Do not output -count and -offset values when the equivalent xml output also omits them for a particular type of list.
Merge branch 'mbs-5726' into beta

* mbs-5726:
  MBS-5726, Do not output -count and -offset values when the equivalent xml output also omits them for a particular type of list.
  MBS-5726, render /ws/2 included discids as "discs" instead of "discids", to be consistent with the XML webservice.
  MBS-5726, add /ws/2/discid json test.
  MBS-5726, implement /ws/2/discid for json webservice.