* Feature - Automatically renew the access credentials.
* Tweak - Keep the settings when disconnecting the Instagram account or removing the plugin.
* Tweak - Remove older update notices on plugin activation.
* Tweak - Added URL verification when connecting and disconnecting the Instagram account.
* Tweak - Increased `timeout` parameter for the API requests.
* Tweak - Added compatibility with WP 5.2.
* Fix - Fixed error when passing a callable as argument to the `empty()` function in PHP 5.4 and lower.
* Dev - Moved Instagram Graph API version to v3.3.
