Add history section for clri(8)

http://minnie.tuhs.org/cgi-bin/utree.pl?file=V6/usr/man/man8/clri.8

PR:		212438
Approved by:	bcr (mentor)
MFC after:	5 days
Differential Revision:	https://reviews.freebsd.org/D8104

sbin/clri/clri.8

@@ -28,7 +28,7 @@
 .\"	@(#)clri.8	8.2 (Berkeley) 4/19/94
 .\" $FreeBSD$
 .\"
-.Dd April 19, 1994
+.Dd October 5, 2016
 .Dt CLRI 8
 .Os
 .Sh NAME
@@ -70,6 +70,11 @@ will be able to clean up the resulting mess.
 .Sh SEE ALSO
 .Xr fsck 8 ,
 .Xr fsdb 8
+.Sh HISTORY
+The
+.Nm
+utility first appeared in
+.At v6 .
 .Sh BUGS
 If the file is open, the work of
 .Nm