* Fixed the handling of quotes and keywords such as "AND", "OR", and "NOT" in LiteralTerm.
Now correct bif:contains or regex filters are created for values.

* Made the query parser merge LiteralTerms into a single one to improve query performance.
While merging two LiteralTerms into one does not yield the exact same query (when merged
both literal tokens need to appear in the same property value while with separate LiteralTerms
the tokens can appear in different properties) it should cover close to all typical use cases
while increasing the performance significantly and getting rid of the nasty "Virtuoso goes
crazy when I use KRunner" bug.