Update tray behavior on linux

[Doka-NT]

In some linux systems hidden windows not available to re-open after hide.

In code was added workaround for that

But some linux supports tray as app is expected, so app have to:

• detect which linux distro is launched. lsb_release -a
• detect desktop environment. echo $XDG_CURRENT_DESKTOP
• hide MainWindow if desktop environment supports it
• In other cases MainWindow should minimize instead of hide

Helpfull links:

• https://askubuntu.com/a/281535

[Doka-NT]

Tray behavior tested on x-cinnamon, unity, kde and xfce.