Ensure "rules" is tab-completable for "queue show"

Previously, tabbing at the end of "queue show" produced a list of
available queues about which information could be shown, but did not
include an alternative command, "rules", to access information about
queue rules. The "rules" item should now be shown in the list of
tab-completable items.

(closes issue AST-958)
Reported-by: John Bigelow
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Merged revisions 372444 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 372445 from http://svn.asterisk.org/svn/asterisk/branches/10
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Merged revisions 372446 from http://svn.asterisk.org/svn/asterisk/branches/11


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@372447 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_queue.c

@@ -8080,6 +8080,12 @@ static char *complete_queue(const char *line, const char *word, int pos, int sta
 	}
 	ao2_iterator_destroy(&queue_iter);
 
+	/* Pretend "rules" is always at the end of the queues list since it is
+	 * an alternate command that should be tab-completable */
+	if (!ret && which == state && !wordlen) {
+		ret = ast_strdup("rules");
+	}
+
 	return ret;
 }