HIPS: AladinLite client on layer mercury_nomenclature_labels

WARNING: http://mapproxy-0:8080/hips/mercury_nomenclature_labels/Norder3/Allsky.png does not exist. It should be pregenerated with "mapproxy-util hips-allsky -f path_to_mapproxy.yaml -l mercury_nomenclature_labels -o 3 -c $(nproc)"