show - hide - raise on trayicon click

[gdamjan]

left click on the tray icon:

• if the window is shown and active, hide it
• if the window is shown but not active, raise/activate it
• if the window is hidden, show/raise/activate it

[gdamjan]

only tested on Linux/KDE though :/

[gdamjan]

wait, there's an issue when the mainwindow is shown on another virtual desktop