Search with non numeric content will not hit number field (it breaks elasticsearch and is useless anyway)
- Rename QueryHelper::buildPrivateFieldQueries() to wrapPrivateFieldQuery().
- Signature changed too, the third parameter is dropped an QueryContext is replaced by an array of Field.
- Query builder closure is now passed an array of Field, not of index field names.
- Remove Field::toConceptPathIndexFieldArray() because method name was beyond understanding (and also because it wasn't needed anymore)
- Various AST node types have changed due to previous API changes
