RDF.hs: added some documentation and moved things around a bit.
RDF.hs: added some documentation and moved things around a bit.

darcs-hash:20071104074738-db1bb-f0af93eb68c25635adfd44d38026641bb0a24e4e

cordawyn/rdf4h,LeifW/rdf4h,ddssff/rdf4h,jutaro/rdf4h