Add ability to export your own user data

[outofambit]

The GDPR website recognizes "The right to data portability" as a right of all people using the internet. While its currently possible to see what data the app has about you in the demo app, there's not way to download that data for yourself. Many places will deliver it in a JSON or CSV format.

We should add a button on the user data page that allows them to download all of their notes and whatever basic personal info we have like email in JSON file.