global: Invenio-Query-Parser with hyphens

* Changes visible name from "Invenio Query Parser" to
  "Invenio-Query-Parser" in order to be consistent with the (lowercase)
  package name.

Signed-off-by: Tibor Simko <tibor.simko@cern.ch>
docs: better description of Invenio-Query-Parser

* Changes description of the Invenio-Query-Parser package in various
  places for better wording describing the search query parser.

Signed-off-by: Tibor Simko <tibor.simko@cern.ch>
docs: removal of explicit Contributors section

* Removes explicit Contributors subsection that was the only one making
  Table of Contents non-flat.

Signed-off-by: Tibor Simko <tibor.simko@cern.ch>