Feature request - Number of tunnel entries in root of tray icon context menu

[wireguard_mailing_list_user at stdmail.de]

Hi,

the hardcoded value is 10 (in ui/tray.go)

Wouldn't it be possible to allow a user to set this value instead of 
using a hardcoded one?

E.g. via:
HKEY_CURRENT_USER\SOFTWARE\WireGuard\TunnelsInRootMenu
Default is 10 and if that registry value doesn't exist, 10 is also the 
default

It should accept values from 0 (display all tunnels) to +x (display at 
maximum x tunnels)

Vertical screen space shouldn't be an issue nowadays and imho the value 
of 10 is a bit too limiting.

Thank you!