Fixes trayicon to work in most conditions.
Fix super-wide dialogs with GTK+ 3.12 and newer

This lets infobars and labels wrap, in dialogs most afflicted by this problem
See https://bugzilla.gnome.org/show_bug.cgi?id=729532 for the context
Make the Preferences dialog's tabs vertical

Being so numerous, they were scrolling, which hurts usability
Fixes for preferences dialog width. (patch by Jeff Fortin)