Add a HISTORY section.

apropos.1

@@ -1,4 +1,4 @@
-.\" $NetBSD: apropos.1,v 1.4 2012/02/20 18:25:51 joerg Exp $
+.\" $NetBSD: apropos.1,v 1.5 2012/04/22 21:27:07 wiz Exp $
 .\"
 .\" Copyright (c) 2011 Abhinav Upadhyay <[email protected]>
 .\" All rights reserved.
@@ -29,7 +29,7 @@
 .\" OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd February 20, 2012
+.Dd April 21, 2012
 .Dt APROPOS 1
 .Os
 .Sh NAME
@@ -114,5 +114,12 @@ The Sqlite FTS database which contains an index of the manual pages.
 .Xr man 1 ,
 .Xr whatis 1 ,
 .Xr makemandb 8
+.Sh HISTORY
+The
+.Nm
+command appeared in 3.0BSD.
+It was rewritten in
+.Nx 6.0
+to support full text search using Sqlite.
 .Sh AUTHORS
 .An Abhinav Upadhyay