NFC cold wallet for Kusama (milestone 2)

This is the work and treasury proposal for milestone 2 of the remaining work described initially here:
https://kusama.polkassembly.io/post/234

Original motion is here:
https://kusama.polkassembly.io/motion/205

Milestone 2 will cover features such as:

• custom derivation paths - derive multiple accounts from single master seed (partially covered in milestone 1)
• export accounts as JSON - ability to import to different wallets
• restore account from JSON (https://polkadot.js.org/apps/#/accounts)
• more options to import already existing wallet mnemonic seed (QR code reader)
• ability to have partial seed backed up on NFC tags (use 2 or more NFC tags to recover the full seed) --> Shamir's Secret Sharing, example: https://iancoleman.io/shamir39/
• finalise PWA website (mostly finished as part of milestone 1)

For milestone 2 we decreased the initial ask from 1000 KSM to 433 KSM due to the recent price appreciation of Kusama and also the fact we managed to cover some tasks as per milestone 1.

It is our pleasure to work with this community and to build awesome stuff for Kusama.

Thanks for the support of all council members and everyone who helped to get this project from idea to "almost" complete app and website.

This is a treasury proposal whose proposer address (Cj73v7pDr15YaKg6cXzbZYft3Vg3ogLiViVYwimmnUFtHmU) is shown in on-chain info below. Only this user can edit this description and the title. If you own this account, login and tell us more about your proposal.