Support for social media links

I have worked on creating this patch to support social media links field. Hope this helps others too.

Ok great, I'll add some tests tomorrow night and get this in.

Thanks!

Ok, should be done
Hows this data shape look?

query {
  node(id: "ccc6baa9-1545-4332-ac48-daedb146dd6a") {
    ... on NodePage {
      social {
        id
        name
        value
        url
        weight
        description
      }
    }
  }
}

Please test on the 2.2.x and let me know if you're happy with that