Fix google

The "name" field returned by the google profile is an object of the format 

```
"name": {
  "familyName": "Bonser",
  "givenName": "Paul"
 }
```

This fix turns it into a string instead, and also uses the displayName attribute of the response since it is there and perhaps might be different.

Also, there's a change to only use the provider_id and provider_user_id when doing a lookup for existing connections.