D21661: add snoretoast backend for KNotifications on Windows

[Piyush Aggarwal]

brute4s99 added a dependency: D21602: Add NSIS Script for KDE Connect.

REPOSITORY
  R289 KNotifications

REVISION DETAIL
  https://phabricator.kde.org/D21661

To: brute4s99
Cc: kde-frameworks-devel, LeGast00n, michaelh, ngraham, bruns