@package: Add-on

Method: LearnDash_Addon_Updater constructor.

Method: Generate plugin updates.

Method: Called when the add-on plugin is upgraded. From the page the user is shown links at the bottom of the page to return to the plugin page or the WordPress updates page. If the user started as the LearnDash Add-ons page we will add the ‘ld-return-addons’ query string parameter. This is used to return the user.