REFERENCE APP: Release Gordian Seed Tool 1.6

[shannona]

Release of GST in coordination with Gordian Coordinator 1.0

• [ ] Finalize Coordinating Features for GST 1.6
• [ ] Support some minimal x-callback function. See http://x-callback-url.com
• [ ] Support more Ethereum specific functions?
• [ ] Add WalletConnect
• [ ] Release GST 1.6
• [ ] Test examples to fit on a NDEF-15 (496 bytes?)
• [ ] Test entirety of 1.6 via Walking through Manual
• [ ] Reshoot all screen shots for GST
• [ ] Update Docs to Support GST 1.6
  • [ ] Update GST Manual
  • [ ] Write UR:PSBT doc.
  • [ ] Write UR:PSBT Section for UR:Crypto-Request Doc
  • [ ] Assess whether there's a way to improve the UR:PSBT Request Test Vectors
  • [ ] Write Integration Doc for Coordinator + GST Usage
  • [ ] Update Multisig Scenario to Use Coordinator as Default, with updates also for GST 1.6
• [ ] Update docs to say techniques only work with English words (not other BIP39 languages)

See also #145.

@WolfMcNally