Faceted search

http://taskman.eionet.europa.eu/issues/10227

Customizes the faceted search and removes the keyword field from search form.

facets available:
 * INSPIRE themes (NEW)
 * organisation
 * types
 * service types
 * GEMET keywords (NEW): filter on thesaurus name to select only GEMET keyword in a new index field
Year
 * Published dataset (NEW): filter records having a publication date and a new index field for them