Support subquestions

[ChrisCoffey]

Description of change

We've encountered the issue described in #13. The problem is that Typeform groups aren't actually questions. They're actually wrappers around lists of questions, so need to be parsed differently from other fields.

Here's an example of the group response from Typeform's field definition:

,
        {
            "id": "t74tqzY6gpow",
            "properties": {
                "button_text": "Continue",
                "fields": [
                    {
                        "id": "ne0ti8xNbxQo",
                        "properties": { 
                        ...
                        },
                        "ref": "21b08fa6-9e91-4e55-9b99-c646b058d246",
                        "title": "What was the first college you applied to?",
                        "type": "dropdown",
                        "validations": {
                            "required": true
                        }
                    },
                    ...
                ],
                "show_button": true
            },
            "ref": "59905e57-02a5-4e4e-b392-6292a52f1309",
            "title": "In this next section, we need some more information about the colleges that you applied to.",
            "type": "group"
        },

Note that each sub-field within the group has id, ref, and title, so they'll parse fine.

What is the best way to test this change?

[cmerrick]

Hi @ChrisCoffey, thanks for your contribution!

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[cmerrick]

You did it @ChrisCoffey!

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[ChrisCoffey]

@pbegle Do you have any advice for testing this change?

[kjarrith]

Any status on this?

[maruskya]

@cmerrick is there any status update on this PR?