Fix the way WsMessage are encoded

ws.go

@@ -15,10 +15,10 @@ import (
 
 // WsMessage is a message from or to the api server
 type WsMessage struct {
-	Title    string
-	CallHash string
-	PeerID   string
-	Data     interface{}
+	Title    string      `json:"title"`
+	CallHash string      `json:"callHash"`
+	PeerID   string      `json:"peerId"`
+	Data     interface{} `json:"data"`
 }
 
 var outMsgChan = make(chan interface{})