Removed the GTK+ indefinite progressbar TODO; the choppiness is correct for GTK+ <= 3.10: http://blogs.gnome.org/mclasen/2013/11/10/smooth-progress/ - mclasen and Company suggest timing with the frame, but this blog post says this will be automatic in 3.12+, so we're good.
Changed Checkbox on Windows to use BS_CHECKBOX instead of BS_AUTOCHECKBOX; this will be necessary to fix the focus issue in todo.md (see http://blogs.msdn.com/b/oldnewthing/archive/2014/05/22/10527522.aspx).
Implemented code to save and restore control focus on Windows properly when switching away from/back to our program. It's disabled for now though because it doesn't seem to work...
Fixed the standard window class focus behavior on Windows from the previous commit to work. Also updated the SetFocus() call in area_windows.go to boot and removed the relevant TODO after checking both wine and Windows XP work fine.