Friendlier error message if bad list parameter specified
Friendlier error message if bad list parameter specified

theodi/publisher,theodi/publisher,telekomatrix/publisher,telekomatrix/publisher,leftees/publisher,alphagov/publisher,leftees/publisher,leftees/publisher,leftees/publisher,telekomatrix/publisher,theodi/publisher,alphagov/publisher,theodi/publisher,alphagov/publisher,telekomatrix/publisher