man page: Bump up release date

Signed-off-by: Sitsofe Wheeler <sitsofe@yahoo.com>
diff --git a/fio.1 b/fio.1
index db2a52b..e910e01 100644
--- a/fio.1
+++ b/fio.1
@@ -1,4 +1,4 @@
-.TH fio 1 "September 2007" "User Manual"
+.TH fio 1 "October 2013" "User Manual"
 .SH NAME
 fio \- flexible I/O tester
 .SH SYNOPSIS