[Evolution] Feature request - Put Evoluton into system tray

[Hamzeh Motahari <hamotahari gmail com>]

Hi,
I have searched about how to send Evolution to the system tray when I push exit or minimize button. But It seems this feature is not implemented. Some popular software like Pidgin or MS Outlook have it and I think it would not a big feature which needs a lot of efforts. 
Of course for now, I use AllTray, but I can't understand why default Ubuntu (GNOME) mail client doesn't have this trivial feature yet.

Does anyone has any idea? 

Thanks