Install automated setup

1) I found a problem that when I run node app --setup='{ "admin:username": "xxx", "admin:password": "xxx", "admin:password:confirm": "xxx", "admin:email": "x" }', the default values below are appended to config.json.

    "redis:host": "127.0.0.1",
    "redis:port": 6379,
    "redis:password": "",
    "redis:database": "",
    "mongo:host": "127.0.0.1",
    "mongo:port": "27017",
    "mongo:username": "",
    "mongo:password": "",
    "mongo:database": "nodebb",

2) I would like a way to set social network logins via automated setup. I am not sure if you currently have the way to do that.