Add in Darwin Core schema support into xml_catalog, and insert it on upgrade as well. The schemas are cached in lib/schema/dwc, and Matt and Ben noted that the tdwg_basetypes.xsd and tdwg_dwctypes.xsd are part of the same namespace, but are xs:include'd rather than imported via namespace.
move the postgres changes to the oracle version -- update note about not attempting to restore because no Oracle MNs exist.
add [partial] upgrade to the oracle script -- does not look for any records that the CN deleted because there are no Oracle-backed MNs at this time.
use v2.4.0 for documentation and upgrade scripts.