Added comment for the [extra] section.

git-svn-id: http://yate.null.ro/svn/yate/trunk@2066 acf43c95-373e-0410-b603-e72c3f656dc1

conf.d/regexroute.conf.sample

@@ -75,6 +75,16 @@
 ;  varname=value
 
 
+[extra]
+; This section allows installing handlers for any message name.
+; Each line must be of the form:
+;  message.name=priority
+; You can only install one handler for any given message name.
+; For each handler create a corresponding [message.name] section in which
+;  implement handling for that specific message. You will need to match
+;  parameters explicitely or set a new match string.
+
+
 [contexts]
 ; This section is used by the prerouting handler to classify calls by the
 ;  caller name; each call is assigned an input context (only if none exists