New intro developer documentation for using QR/UR for seeds

[ChristopherA]

We have a new PR from @shannona that offers a developer introduction to our QR/UR specifications, and walks you through using QR/UR for seeds, secret shares, and hd-keys.

https://github.com/BlockchainCommons/crypto-commons/pull/3/files

Comments and clarifications welcome before we merge this PR.

More to come over the next month, including how do do crypto-request, account maps, PSBT, and more using QR/UR.

Let us know what other documentation or tools that we should work on to help enable you to better support QR/UR in your wallets.

-- Christopher Allen

[ChristopherA]

These new documents are available now:

• Overview of Uniform Resources (URs)
• A Guide to Using URs for Key Material

More to come over the next month, including how do do crypto-request, account maps, PSBT, and more using QR/UR.

-- Christopher Allen