Add Tezos address to the donate panel

[Alex Bainter]

Address: tz1YdFTttJwg8um2fBGHTVgUxyQUd2ApzCag

• Create a QR code with the address as the content using https://www.the-qrcode-generator.com.
  • Other cryptos have a prefix like "btc:", does Tezos have one?
• Add the QR code image to this directory.
• Add Tezos to the crypto picker.