we put up a dialog before we auto migrate. (the mozilla build does this.)
if that pref is false, we just automigrate. (the ns build does this.)
r=bienvenu
r=sspitzer
I made changes so that:
1) exit quits the app, and doesn't start up app with the last current profile
2) fix a spelling error (personalisation -> personalization), this is en-US, not en-UK
3) fix it so start actually starts the selected profile.
4) -SelectProfile launches this new dialog
5) if the user starts with no command line, and they have more than one profile, they get -SelectProfile, and not -installer.
