expand code based appreviation of AST_CONFIG_DIR to configuration directory

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@243652 65c4cc65-6c06-0410-ace0-fbb531ad65f3

CHANGES

@@ -390,7 +390,7 @@ Miscellaneous
    This allows #exec to be used in asterisk.conf.
  * jabber.conf supports a new option auth_policy that toggles auto user registration.
  * A new lockconfdir option has been added to asterisk.conf to protect the
-   AST_CONFIG_DIR during reloads.
+   configuration directory (/etc/asterisk by default) during reloads.
 
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 --- Functionality changes from Asterisk 1.6.1 to Asterisk 1.6.2  -------------