remove a key error relating to auth_mode on first use of strudel
Layout changes

Change a radiobox to a combobox for use ssh keys verse use password
change the vertical alignment of various statictext elements so they
don't look quite so odd anymore.
slight improvements to the siteListDialog, buttons right aligned, columns expand when windowsize is changed
show the network fault dialog when the tunnels disapear. Actually this is a little agressive since the dialog will be shown if the session terminates due to walltime as well