Removed broken link and fixed incorrect id in url

[SavPhill]

Removed link on line 520 which was broken - http://sourceforge.net/p/bitcoin/mailman/message/31709140/.

Edited the url of the wikipedia to reflect the correct scroll to it for Simplified Payment Verification.
From https://en.bitcoin.it/wiki/Scalability#Simplifiedpaymentverification to https://en.bitcoin.it/wiki/Scalability#Simplified_payment_verification

Description

1. Fixing a broken link to a resource which is no longer available.
2. Editing the url of a link to make the id instantly accessible.

Related Issue

1. Visit the link titled Peter Todd on Merkle sum trees on point 21 of Further Reading: http://sourceforge.net/p/bitcoin/mailman/message/31709140/
   It is no longer accessible.
2. Visit the link titled Simplified payment verification on point 13 of further reading: https://en.bitcoin.it/wiki/Scalability#Simplified_payment_verification. The scroll to ID is incorrect and it opens the top of the page, which makes the link appear incorrect initially for the user.

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Name	Status	Preview	Updated
ethereum-org-website	✅ Ready (Inspect)	Visit Preview	Sep 5, 2022 at 5:22PM (UTC)

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[minimalsm]

Hey @SavPhill, thanks for catching this.

We decided that we would not be alterating the Whitepaper (checkout #3794 for context), apart from fixing things that are broke. So we'd definitely want to keep the Peter Todd further reading link.

Luckily, we have a web archive version of the Peter Todd on Merkle sum trees that we can use instead: https://web.archive.org/web/20140623061815/http://sourceforge.net/p/bitcoin/mailman/message/31709140/

[SavPhill]

Hey @SavPhill, thanks for catching this.

We decided that we would not be alterating the Whitepaper (checkout #3794 for context), apart from fixing things that are broke. So we'd definitely want to keep the Peter Todd further reading link.

Luckily, we have a web archive version of the Peter Todd on Merkle sum trees that we can use instead: https://web.archive.org/web/20140623061815/http://sourceforge.net/p/bitcoin/mailman/message/31709140/

Thank you- new commit made with the edit:

a3a7a49

[corwintines]

Thanks for fixing these broken links @SavPhill!

[corwintines]

@all-contributors can you add @SavPhill for docs

[allcontributors]

@corwintines

I've put up a pull request to add @SavPhill! 🎉