文档有更新：发送视频的客服消息

http://mp.weixin.qq.com/wiki/index.php?title=%E5%8F%91%E9%80%81%E5%AE%A2%E6%9C%8D%E6%B6%88%E6%81%AF
发送视频消息
{
    "touser":"OPENID",
    "msgtype":"video",
    "video":
    {
      "media_id":"MEDIA_ID",
      "title":"TITLE",
      "description":"DESCRIPTION"
    }
}