Add claim website

[blechschmidt]

I have added a method to generate the proof through a website, which performs the computations and only asks the user to decrypt the temporary Ethereum address through age manually. This eliminates a huge amount of trust users need to put into code accessing their private keys while maintaining a reasonable degree of usability.

If you enabled CORS on https://fluence-dao.s3.eu-west-1.amazonaws.com/metadata.json, the intermediate step of downloading the metadata.json file could be dropped and the HTML could be directly hosted on some public web server.

PS: By the way, thanks for the airdrop.

Disclaimer: I am not affiliated with the Fluence project.