docs: JSON data structure

[haruki7049]

JSON data structure

It has:

• user-name
• device-name
• device-hash

[haruki7049]

[
  {
    "username": "haruki7049",
    "device": [
      {
        "name": "phone",
        "hash": ""
      }
    ]
  }
]

[haruki7049]

STUNサーバーにグローバルIPとポートを求めて、その情報をexchanに定期的に渡す（IPの変更を検知する）

[haruki7049]

confidential info

[
  {
    "daemon_hash": "~~~",
    "ip": "111.111.111.111",
    "port": "99999"
  }
]