Fix some consistency issues with jitterbuffer config.

Store the defaults noted in the sample config files in the jitterbuffer config
data structure.  This makes the CLI commands that output these settings show
the right thing.  Also only show the settings that are relevant in the settings
CLI commands, based on which jitterbuffer is selected and whether it's enabled.

(closes issue #19083)
Reported by: rgagnon
Patches:
      issue-19083-trunk-r313139.diff uploaded by rgagnon (license 1202)


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.8@317478 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_console.c

@@ -172,13 +172,14 @@ AST_RWLOCK_DEFINE_STATIC(active_lock);
  * \brief Global jitterbuffer configuration 
  *
  * \note Disabled by default.
+ * \note Values shown here match the defaults shown in console.conf.sample
  */
 static struct ast_jb_conf default_jbconf = {
 	.flags = 0,
-	.max_size = -1,
-	.resync_threshold = -1,
-	.impl = "",
-	.target_extra = -1,
+	.max_size = 200,
+	.resync_threshold = 1000,
+	.impl = "fixed",
+	.target_extra = 40,
 };
 static struct ast_jb_conf global_jbconf;