Do not redraw roster when opening the accounts window. Rework preference window. Fixes #3330, #1621, #2113

add checkbutton to YesNoDialog. Ability to fall back from tls to ssl and then plain. Warn user when using insecure connection. fixes #1923

[sgala] nicer code. No need to change contact's status to offline when we go offline if contact is already offline. see #3718

padlock icon in merged accounts mode: show when all connected accounts are connected securely, don't show it when one is not secured, do no care about offline accounts.

Remove saveposition. Now we always save and restore positions and sizes. See #3638. steve-e, this bug
is still opened for what you told ;)