Referral System for WooCommerce 1.4.4

* Remove Mixpanel Integrattion.

* Minor improvements and optimizations.

* Fixed an issue where setting a custom referral URL through a filter did not work correctly

* Compatibility with HPOS and Custom order table.

* Added - Template Overriding Support – Allowing customization of the referral link tab on the storefront.

* translation error resolved.

* Php Compatibility issue fixed.

* Sniffer Error Resolved.

* sniffer error resolved.

* Code Sniffer Error - Resolve plugin sniffer error