Discuss and implement place verification workflow

[dadofsambonzuki]

On the verification of locations by Cash App users, we have two options:

1. Direct users to the verification form (location ID as query parameter) on btcmap.org. e.g.https://btcmap.org/verify-location?id=<btcmap-id>.
2. Have Cash App hit a /verify_place endpoint with the details.

Note: this is separate to the revoke_submitted_place endpoint that is to be solely used when a Square merchant has removed themselves from BTC acceptance via the off-boarding process.

[dadofsambonzuki]

This is also something other wallet providers have expressed an interest in.