Mention that BIP350 proposes to reduce the scope of BIP173 to Native Segwit v0

[murchandamus]

This is a follow-up to #945 to reduce the scope of BIP173 to native segwit v0.

I expect that you may have feedback about the phrasing, @sipa.

[sipa]

I think it suffices to add:

• a comment about the discovered weakness in the checksum scheme
• a reference to BIP-350 saying "Because of (that weakness), BIP-350 proposes using the scheme described in this BIP only for Witness v0 outputs."
• A "Superseded-By: 350" header.

That avoids actually changing what BIP-173 proposed, even though we now know that wasn't ideal.

[sipa]

ACK 7a10449

[vostrnad]

Looks like you accidentally deleted most of the changes during a force push?

Edit: Never mind, looks like it wasn't accidental, however I feel like the PR title should have been updated.

[sipa]

@vostrnad I objected offline about the title change and other changes.

BIP173, for better or worse, still refers to the idea of using Bech32 for all Native Witness outputs. It has been largely supplanted by BIP350, and it now makes note of that, but we shouldn't be retroactively changing what the idea of BIP173 was.

Nevermind, you're referring to the PR title, not the BIP title?

[vostrnad]

Yes, the PR title (and consequently the merge commit) still talks about changing the scope. Nothing serious, but I'd still prefer for future PRs to have just a little more time for outside review.