Fix/messenger button name

[killix]

This button:

  {
    "type": "Button",
    "name": "postback_name",
    "content": "Try it the postback!",
    "url": "payload_postback"
  }

return now:

object:
 { content: 'payload_postback',
   id: '1505767221011',
   type: 'Note',
   name: 'Try it the postback!' }