Keyword / improve relation search (#147)

* KeywordBean / Remove simple String broader field which could be multiple
* Regions / Category is the first broader relation found
* Fix duplicates in search results (due to broader in select clause)
* Fix search for broader/related/narrower relation types
* Fix searchForRelated which does not return List<KeywordBean> like search does
Merge pull request #149 from fxprunayre/improvement/keyword-search-relation

Keyword / improve relation search (#147)
Harvester / Error retrieving remote node groups (#150).
Merge pull request #151 from fxprunayre/bugfix/150-harvester-geonet

Harvester / Error retrieving remote node groups (#150).
Merge remote-tracking branch 'upstream/develop'