UI change to GDM

[Brian Cameron <Brian Cameron Sun COM>]

I realize it is past the UI freeze date, but to fix bug #145549, it is
necessary to make a small change to the UI.  gdmsetup currently has a
checkbox to decide if the user wants a 12 hour or 24 hour clock to be
shown in GDM.  To fix the bug, we need to change this to a dropdown
list where the user can pick "12 hour", "24 hour" or "auto".  The
new "auto" setting gets the format from the LC_TIME environment
variable so that GDM looks more consistant with other applications.

Is it okay to make this change?

Brian