[bd] Widget Framework 2.6.6

Change logs (since 2.5.9)

- PHP 7.2 compatibility
- Redesigned Layout Editor
- Performance improvements
- Added: Profile Posts renderer
- Added: Layouts in Threads renderer
- Added: User Follow, User Info renderer
- Added: XenForo Media Gallery support
- Added: Widget page’s widgets import / export
- Added: Cache Store option
- Changed: Expression is deprecated, it’s recommended to use Conditionals