[Feature] hokey for functions in main menu

[Hofknecht]

There should be hotkeys for the functions in main menu?

and maybe tooltip to show the user the shortcut?

[Hofknecht]

maybe like this, we should then extend the readme

Shortcut	Function
O	Open current menu in Win Explorer (not yet implemented)
P	Pin to taskbar (not yet implemented)
S	Open Settings menu (not yet implemented)
R	Refresh SytemTrayMenu (not yet implemented)
Ctrl+c	Copy selected item into clipboard (not yet implemented)
Ctrl+v	Paste selected item from clipboard (not yet implemented)