mappings/VegCore-VegBIEN.csv: locationID/locationName + subplot -> location.sourceaccessioncode mapping: Fixed bug where subplot was incorrectly being mapped to this field even when there was no location*. (This field can only be populated if both location* and subplot are specified.) Also only map locationID for this, to avoid inconsistencies where one table supplies locationID+subplot, while another table supplies locationName+subplot, but they both get mapped to the same field, preventing plots from being matched up with their observations when creating the analytical_stem.