Re: Fix for normalization of foreign idents

>   $Id: blah$ --(c_t_w_t)--> $Id: blah$ --(c_t_g)--> $Id: blah$
> 
> This restores correct and deterministic operation of status and
> diff, meaning that if the file hasn't actually been modified, no
> modifications are shown.
> 
> As you might suggest, always keeping the foreign ident would mean it
> is never updated when you commit new versions of the file, which isn't
> really what we want.  Keeping the foreign ident as long as the last
> modification to the file was made in the previous version control
> system makes perfect sense, but once we make a commit to the file
> within git, it should be replaced with a git ident.