WooCommerce Smart Coupons 8.23.0

* New: WooCommerce 3.5.1 compatibility
* Fix: Searching coupon in shortcode pop-up is showing duplicate results
* Fix: New coupon designs not applying on preview of coupon in shortcode pop-up
* Fix: On removing coupon from checkout page, available coupon list not refreshing
* Fix: On clicking coupon, there's no indication of whether coupon is applying or not
* Fix: Broken HTML code in emails when the order is fully paid by store credit
* Fix: Logging error for WC lower than 3.0.0
* Fix: 'Coupon Receiver Detail' form on checkout page not showing correctly on few themes
* Update: Improved CSS for 'Coupon Receiver Detail' form on checkout page
* Update: sample.csv
* Update: POT File

* New: Customizable Coupon designs
* Fix: Restrict single-use coupon to biling email address of guest user
* Fix: Correction in function arguments
* Fix: Show/hide of coupon not working correctly on checkout page
* Fix: Responsiveness of Welcome page
* Update: POT File

* Fix: Store Credit not applying discount on manual renewal (WooCommerce Subscriptions)