FIX test TestSemanticURIGuesser ; rename RDFCacheJena as RDFCache

TODO : TestCreationForm2 fails in NPE when accessing ops via FOAPPrefix
pave the way for replacing Jena call RDFDataMgr.loadModel() by (porposed) generic Banana RDF : anyRDFReader.readAnyRDFSyntax()

Try to fix TestCreationForm2.scala : currently infinite loop in Prefix.apply() in eclipse
update README with UI tasks