Fix "cancel answered elsewhere" through app_queue with members in chan_local.

Also, implement a private cause code (as suggested by Tilghman). This works with
chan_sip, but doesn't propagate through chan_local.



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@172318 65c4cc65-6c06-0410-ace0-fbb531ad65f3

include/asterisk/causes.h

@@ -81,6 +81,10 @@ specification:
 	- AST_CAUSE_PROTOCOL_ERROR			111
 	- AST_CAUSE_INTERWORKING				127
 
+The range 128-255 is private cause codes. Our private causes are:
+
+	- AST_CAUSE_ANSWERED_ELSEWHERE			200
+
 For more information:
 - \ref app_dial.c
 */
@@ -136,6 +140,9 @@ For more information:
 #define AST_CAUSE_PROTOCOL_ERROR			111
 #define AST_CAUSE_INTERWORKING				127
 
+/* Private Cause codes for Asterisk */
+#define AST_CAUSE_ANSWERED_ELSEWHERE			200
+
 /* Special Asterisk aliases */
 #define AST_CAUSE_BUSY 					AST_CAUSE_USER_BUSY
 #define AST_CAUSE_FAILURE 				AST_CAUSE_NETWORK_OUT_OF_ORDER