Make fstat(1) show socket endpoints information

[Jeremie Le Hen]

Hey folks,

I resurrected this Bugzilla entry [1] which adds an option to fstat(1)
so that it shows sockets' endpoint(s) information.

The initial proposal was adding the "-i" flag because it was working
only for inet/inet6 sockets but the new patch also works for
unix/local sockets, so I renamed the flag "-s".

I created a Phabricator entry for the new patch:
https://reviews.freebsd.org/D21880
This contains a sample output for local/internet sockets.

Let me know what you think.
Cheers,

[1] https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=116643
-- 
Jeremie Le Hen
jlh at FreeBSD.org