A facet type for creating a list of filterable price / number ranges.
- Fix: refactored code to better support for the Fetch API
- Fix: prevent from overwriting user-defined range labels
- Changed `wp.hooks` to `FWP.hooks` due to conflict with WP 5.0
- Refactor to support JS deferring
- This add-on now requires FWP 3.2.0+
- Fixed bug if the value = end of range (props @pourri-dixit)