DOC: stick-table: modify the description

The stickiness table can be declared in such sections as frontend, listen
and backend, but the original manual only mentioned backend. Modify the
description simply as below:
	"current backend" -> "current section"

Signed-off-by: Godbach <nylzhaowei@gmail.com>
diff --git a/doc/configuration.txt b/doc/configuration.txt
index 803d42e..81b4295 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -6133,7 +6133,7 @@
 stick-table type {ip | integer | string [len <length>] | binary [len <length>]}
             size <size> [expire <expire>] [nopurge] [peers <peersect>]
             [store <data_type>]*
-  Configure the stickiness table for the current backend
+  Configure the stickiness table for the current section
   May be used in sections :   defaults | frontend | listen | backend
                                  no    |    yes   |   yes  |   yes