WooCommerce Advanced Product Labels 1.3.1

* [Fix] - Featured condition not matching in cases after WC 3.0
* [Fix] - PHP 7.1 notice {discount} is used when sale price is not set
* [Improvement] - Small style fix for Storefront (should also help other themes)

* [Improvement] - Update WP Conditions to 1.0.3
- [Fix] - 'User role' condition 'Guest' wasn't working
- [Improvement] - Allow conditions outside postbox / multiple times inside. Not limited to .postbox class.
- [Add] - Zipcode range support. E.g. 'Zipcode' = 'equal to' = '10000-20000,30000-40000'

* [Add] - Support for 'Guest user' on the 'User role' condition
* [Improvement] - Further improvements to prevent WC 3.0 notices
* [Fix] - Random IDs for conditions being too big for 32-bit systems