Merge pull request #120 from dfeyer/bugfix-escape-slash

TASK: Proper escaping for slash in full text query

Without escaping ElasticSearch return an error for the current query.

Author: dfeyer

Classes/Flowpack/ElasticSearch/ContentRepositoryAdaptor/Eel/ElasticSearchQueryBuilder.php

@@ -726,7 +726,7 @@ public function fulltext($searchWord)
     {
         $this->appendAtPath('query.filtered.query.bool.must', [
             'query_string' => [
-                'query' => $searchWord
+                'query' => json_encode((string)$searchWord)
             ]
         ]);