ReadMe: add blurb about Advanced Recurring.

readme.txt

@@ -90,6 +90,7 @@ Extend Sugar Calendar with these free add-ons. We keep the plugin lightweight by
 
 If you purchase an [Ultimate or Professional license](https://sugarcalendar.com/pricing/?utm_medium=referral&utm_source=website&utm_campaign=wporg-scl-plugin-page) to Sugar Calendar you get access to all current and future pro add-ons.
 
+- **[Advanced Recurring](https://sugarcalendar.com/downloads/advanced-recurring/?utm_medium=referral&utm_source=website&utm_campaign=wporg-scl-plugin-page)** - This add-on allows you to setup any type of recurring event. Daily, weekly, monthly, and yearly frequencies each have support for Intervals. Day-of-Week, Day-of-Month, and Month-of-Year allow for events to have multiple occurrences. Ordinals allow events to occur on the 2nd Monday, last Friday, and so on. Recurring can stop after a specific date, number of occurrences, or never.
 - **[Event Ticketing](https://sugarcalendar.com/downloads/event-tickets/?utm_medium=referral&utm_source=website&utm_campaign=wporg-scl-plugin-page)** - This add-on allows you to easily sell tickets to your events, whether they are virtual or in-person events. The plugin includes complete order and ticket management, attendee records, emailed and print versions of tickets, and a direct integration with [Stripe](https://stripe.com/) for payment processing. Easily integrates with WooCommerce to allow event tickets to be purchased through existing WooCommerce checkout pages.
 - **[Frontend Event Submissions](https://sugarcalendar.com/downloads/frontend-event-submissions/?utm_medium=referral&utm_source=website&utm_campaign=wporg-scl-plugin-page)** - This add-on allows you to set up event submission forms that provide a way for your community members to create their own events in your calendars.
 - **[Calendar Feeds](https://sugarcalendar.com/downloads/calendar-feeds/?utm_medium=referral&utm_source=website&utm_campaign=wporg-scl-plugin-page)** - Easily subscribe to Events feeds for any of your calendars in Sugar Calendar from Google Calendar, iCal, Gnome Calendar, or just about any other calendar application.