we upgrade sub and ask status in the plugins when we recieve them

some Jabber servers doesn't understand http://jabber.org/protocol/disco#items (jabber.sk don't) so use jabber:iq:browse instead

- it is now possible not to save the passphrase for accounts
- close button in accounts window
- unset sensitivity of some widgets in preferences window when some checkboxes are not active
- autoconnect accounts is now available
- apply button in preferences window

When an account is not active, it is not touched by optionmenu changes, but can be specifically changed.