code: public void stopStream(Stream stream, final KickflipCallback cb) {
          if (!assertActiveUserAvailable(cb)) return;
          stopStream(getActiveUser(), stream, cb);
      }
docs: Stop a Stream. Must be called after
  {@link io.kickflip.sdk.api.KickflipApiClient#createNewUser(KickflipCallback)} and
  {@link io.kickflip.sdk.api.KickflipApiClient#startStream(io.kickflip.sdk.api.json.Stream, KickflipCallback)}
  
  @param cb This callback will receive a Stream subclass in {@link io.kickflip.sdk.api.KickflipCallback#onSuccess(io.kickflip.sdk.api.json.Response)}
  depending on the Kickflip account type. Implementors should
  check if the response is instanceof HlsStream, etc.