Some visual fixes here and there

Bump NetStalker to v4.0.

Various small visual updates

Fix a possible exception when a "choice" key wasn't found in the toas…

…t arguments.

Remove unwanted stuff.

Code refactorings and changes based on the new SharpPcap.

Upgrade to 2.2.1

Switched from Winpcap to Npcap driver and added a Npcap driver check

Fixed a small bug in app configuration

Preparations for v2.0

- Fixed a bug in the spoof protection mechanism.
- Fixed a bug related to the tray icon's context menu.
- Fixed a bug related to blocking newly discovered devices from toast notifications.
- Code refactorings.