Allow empty string when serializing paths (typical default value).
Allow empty string when serializing paths (typical default value).

liqd/adhocracy3.mercator,liqd/adhocracy3.mercator,xs2maverick/adhocracy3.mercator,fhartwig/adhocracy3.mercator,xs2maverick/adhocracy3.mercator,fhartwig/adhocracy3.mercator,xs2maverick/adhocracy3.mercator,fhartwig/adhocracy3.mercator,fhartwig/adhocracy3.mercator,xs2maverick/adhocracy3.mercator,fhartwig/adhocracy3.mercator,liqd/adhocracy3.mercator,fhartwig/adhocracy3.mercator,fhartwig/adhocracy3.mercator,liqd/adhocracy3.mercator,liqd/adhocracy3.mercator,liqd/adhocracy3.mercator,liqd/adhocracy3.mercator,xs2maverick/adhocracy3.mercator,xs2maverick/adhocracy3.mercator