Do not run elevated by default (#884)

Make the runner not run as elevated by default. Add a setting for
"run PowerToys as elevated" and buttons to restart the process
with the different elevation levels.

src/runner/tray_icon.h

@@ -1,6 +1,8 @@
 #pragma once
 // Start the Tray Icon
 void start_tray_icon();
+// Stop the Tray Icon
+void stop_tray_icon();
 // Open the Settings Window
 void open_settings_window();
 // Callback type to be called by the tray icon loop