assetseed: Update to work with the current seed format.

[JoeGruffins]

We have an app at /client/cmd/assetseed. It only works with the old hex format but should work for both that one and the newer 15 word seed.

I wonder if we could also spit out something for bitcoin clones that a user can use to import into whatever core wallet. eth can already do this from the UI I believe. mentioned here #3105 (comment)

Does the seed work with Bitcoin core?

[dev-warrior777]

Will try BTC

[freQniK]

Nice. So I could do asset=2 with the Bison seed and it should give me the raw hex private key of the litecoin wallet?

I don't need this now as I switched my Litecoin wallet to my Litecoin core node, but would be good to know for other users.

[JoeGruffins]

No, I looked into it and the seed is not compatible with bitcoin/litecoin core, sadly. I don't think there's anything we can do to restore internal wallets with other software.

[freQniK]

No, I looked into it and the seed is not compatible with bitcoin/litecoin core, sadly. I don't think there's anything we can do to restore internal wallets with other software.

Ahh. This is probably why when I wrote a python script to produce the private key from the Bison seed, I couldn't get it to produce the same wallet in other Litecoin wallets like electrum. I kept thinking I was doing something wrong.