Merge branch 'master' of https://github.com/molgenis/molgenis into feature/virtualRepository

                                 Conflicts:
                                 	molgenis-data-elasticsearch/src/main/java/org/molgenis/data/elasticsearch/ElasticsearchRepositoryDecorator.java
                                 	molgenis-search-elasticsearch/src/main/java/org/molgenis/elasticsearch/index/MappingsBuilder.java
                                 +bugfix for filter wizard (#1815)

+ refactor repository merger
+unittest repository merger