Repaired issue with rdf hierarchy not re-importing. Not fully sure when this stopped working. Seems to be related to ARC parser version. Looks like previously it returned a list of predicate targets indexed by target ID. This was replaced with a numeric index now? So the lookup for do-i-know-this-term-already went back to the DB, and pulled a fresh copy into the relinker script. The fresh copy did NOT have the additional linking info that was loaded a second before. Hm. Still may need testing on the other formats, but the patch was designed to allow both indexed and non-indexed inputs to work.
big rewrite to make rdf export D7-style SKOS instead of w3C thesaurus. Ended up rewriting half of D7 RDF again to make it think the same as D7. many silly RDF libraries, need to gather them together again I think.
module_invoke_all('rdf_namespaces') can't be used now that some modules are actually finally using it - duplicates merge incorrectly. replacing it with rdf_get_namespaces() - which flattens it