add missing copyright info

doc/recover.6

@@ -1,6 +1,17 @@
-.TH RECOVER 6 "9 January 1993"
-.\" NetHack 3.6  recover.6	$NHDT-Date: 1450129883 2015/12/14 21:51:23 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.8 $
-.UC 4
+.TH RECOVER 6 "14 December 2015" NETHACK
+.de ND
+.ds Nd \\$3
+..
+.de NB
+.ds Nb \\$2
+..
+.de NR
+.ds Nr \\$2
+..
+.ND $NHDT-Date: 1524689550 2018/04/25 20:52:30 $
+.NB $NHDT-Branch: NetHack-3.6.0 $
+.NR $NHDT-Revision: 1.9 $
+.ds Na Kenneth Lorber
 .SH NAME
 recover \- recover a NetHack game interrupted by disaster
 .SH SYNOPSIS
@@ -130,3 +141,7 @@ determine.
 .I recover
 should be taught to use the nethack playground locking mechanism to
 avoid conflicts.
+.SH COPYRIGHT
+This file is Copyright (C) \*(Na and was last modified \*(Nd (version
+\*(Nb:\*(Nr).
+NetHack may be freely redistributed.  See license for details.