RDF serializer fix
- implement support for Rdf conversion of statements with properties
which have MonolingualText as primitive type
add licence header
implement translation from wikidata language encoding to BCP 47
add test for MonolingualTextValueConverter
Merge remote-tracking branch 'origin/monolingualTextValueSupportBugFix' into conversation-comandLine-client
change parser
	- change version in pom file
	- change dump format from xml to json