Add output type to mqtt node

Fixes #1912

nodes/core/locales/en-US/messages.json

@@ -324,6 +324,7 @@
         "label": {
             "broker": "Server",
             "example": "e.g. localhost",
+            "output": "Output",
             "qos": "QoS",
             "retain": "Retain",
             "clientid": "Client ID",
@@ -358,6 +359,10 @@
             "connect-failed": "Connection failed to broker: __broker__"
         },
         "retain": "Retain",
+        "output": {
+            "buffer": "a Buffer",
+            "string": "a String"
+        },
         "true": "true",
         "false": "false",
         "tip": "Tip: Leave topic, qos or retain blank if you want to set them via msg properties.",

nodes/core/locales/ja/messages.json

@@ -324,6 +324,7 @@
         "label": {
             "broker": "サーバ",
             "example": "例) localhost",
+            "output": "出力",
             "qos": "QoS",
             "retain": "保持",
             "clientid": "クライアント",
@@ -358,6 +359,10 @@
             "connect-failed": "ブローカへの接続に失敗しました: __broker__"
         },
         "retain": "保持",
+        "output": {
+            "buffer": "バイナリバッファ",
+            "string": "文字列"
+        },
         "true": "する",
         "false": "しない",
         "tip": "注釈: トピックやQoSをメッセージのプロパティを用いて設定する場合は、無記入にしてください。",

nodes/core/locales/zh-CN/messages.json

@@ -314,6 +314,7 @@
         "label": {
             "broker": "服务端",
             "example": "e.g. localhost",
+            "output": "输出",
             "qos": "QoS",
             "clientid": "客户端ID",
             "port": "端口",
@@ -342,6 +343,10 @@
             "connect-failed": "与服务端 __broker__ 的连接失败"
         },
         "retain": "保留",
+        "output": {
+            "buffer": "Buffer",
+            "string": "字符串"
+        },
         "true": "是",
         "false": "否",
         "tip": "提示: 若希望通过msg属性对topic(信息), qos及retain(保留)进行设置, 则将上述项留白",