Rewrite page(2) references to page(3).

Add description of new libmach.
diff --git a/man/man3/authsrv.3 b/man/man3/authsrv.3
index 65aebef..d9286dc 100644
--- a/man/man3/authsrv.3
+++ b/man/man3/authsrv.3
@@ -215,7 +215,7 @@
 .SH SEE ALSO
 .IR passwd (1),
 .IR cons (3),
-.IR dial (2),
+.IR dial (3),
 .IR authsrv (6),
 .SH DIAGNOSTICS
 These routines set