mappings: Build VegX-VegBIEN.organisms.csv from VegX-VegBIEN.stems.csv instead of vice versa. This entails switching the roots around so stem points to organism instead of the other way around, which is a complex operation. Re-rooted VegX-VegBIEN.organisms.csv at /plantobservation instead of /taxonoccurrence to avoid traveling up the hierarchy to taxonoccurrence and back down again to plantobservation, etc. as would otherwise have been the case.