Handle failing INSERTs gracefully during gauges import Using the special table EXCLUDED in INSERT statements makes functionally no difference, but makes editing of the statements easier. Since reference water levels are not deleted all at once before (re-)importing anymore, take the chance to report those that were deleted.

teichmann@intevation.de = sascha.teichmann@intevation.de
bernhard.reiter@intevation.de = bernhard@intevation.de