[help] Change string format of summary line

Additionally show rdfs:label value when available
[autocomplete] Update XSL algorithm for shortening resource identifiers

Now rdf:about values can be shortened regardless of their notation
(http://foo.com/myResource, http://foo.com/myResource#myResource,
myResource) and documentation about the current vocab/ontology document
are ignored (will be undone in future release).
Update README and add screenshots