support kill dial if sd ep is media timeout (#1001)

* support kill dial if sd ep is media timeout

* support kill dial if sd ep is media timeout

* support kill dial if sd ep is media timeout

* add media timeout reason header to bye message

* wip

* wip

* make configuration for freeswitch media timeout

* make configuration for freeswitch media timeout

* wip

lib/utils/constants.json

@@ -196,7 +196,8 @@
   },
   "KillReason": {
     "Hangup": "hangup",
-    "Replaced": "replaced"
+    "Replaced": "replaced",
+    "MediaTimeout": "media_timeout"
   },
   "HookMsgTypes": [
     "session:new",