Map Walkthrough: Add a tutorial walkthrough according to Google Doc

Example implementation: http://codeforboston.github.io/ungentry/
Previously that project used https://bootstraptour.com but that may not be the best option in this case.

- [ ] Please research React alternatives to bootstrap tour like https://www.npmjs.com/package/intro.js-react
- [ ] Make a basic implementation on one page
- [ ] Add the other pages according to the reference document below
- [ ] Repeat users do not see the tutorial again

(Welcome to break these down to smaller issues)

Reference for text: https://docs.google.com/document/d/1OgQOdMkVXc8kH7pkQa3IBmqbBdU-1Q2ROkgov-9vD6M/edit