Uncanny Owl In-plugin Notifications

• Run this command in console to add notifications as a dependent
  • git submodule add https://github.com/UncannyOwl/Uncanny-Owl-In-Plugin-Notifications.git src/notifications
• Update using git submodule update --remote
• Include the notifications module by doing:
  • `require_once DIR . '/your/path/to/notifications/notifications.php';