Misimplemented object type

[sztanko]

"params": {
      "type": "object",
      "$ref": "#/definitions/DBConnection"
    },```

translates to: 

```self.params: Optional[Dict] = data.get('params')```

The only way to make it an object is to have it like this:

"params": {
  "type": "object",
  "oneOf": [{ "$ref": "#/definitions/DBConnection" }]
},```

I would like to have the first jsonschema implemented as well.