Completely remove old (non-segwit) transaction support

[van-orton]

Problem description

The code of BGL core is derived from Bitcoin core with some changes. The BTC is switching gradually to segwit transactions, while allowing older txs and addresses to still work. In BGL, those legacy transactions are not required.
In other words, remove support for P2PK[H] to be sure no 'old' transaction can be made, and leave only SegWit transactions supported.

Solution direction

• carefully check in source code where transaction types are detected or formed;
• remove support for legacy transaction types where applicable;
• tread lightly, don't remove something if unsure;

Acceptance criteria

• Old transaction types cannot be created though CLI/wallet, validated, etc.

[gitcoinbot]

Issue Status: 1. Open 2. Started 3. Submitted 4. Done

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This issue now has a funding of 1.0419 ETH (400.01 USD @ $383.93/ETH) attached to it.

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[gitcoinbot]

Issue Status: 1. Open 2. Started 3. Submitted 4. Done

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Work has been started.

These users each claimed they can complete the work by 266 years, 1 month from now.
Please review their action plans below:

1) developerfred has been approved to start work.

I will remove support for old addresses and ensure that no transactions take place with the old format. Checked all source code carefully.
2) janus has applied to start work (Funders only: approve worker | reject worker).

I recently worked for a client that encoded and decoded a large number of addresses from diverse blockchain networks. I have gained great skill in the area of address structure and format. I would apply this knowledge while carrying out your task. This task would be completed in days.

Learn more on the Gitcoin Issue Details page.

[gitcoinbot]

@developerfred Hello from Gitcoin Core - are you still working on this issue? Please submit a WIP PR or comment back within the next 3 days or you will be removed from this ticket and it will be returned to an ‘Open’ status. Please let us know if you have questions!

• reminder (3 days)
• escalation to mods (6 days)

Funders only: Snooze warnings for 1 day | 3 days | 5 days | 10 days | 100 days

[developerfred]

Ok I will submit PR working progress today

[gitcoinbot]

Issue Status: 1. Open 2. Started 3. Submitted 4. Done

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Work for 1.0419 ETH (381.95 USD @ $367.25/ETH) has been submitted by:

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• $891,679.85 more funded OSS Work available on the Gitcoin Issue Explorer

[ayushkumar63123]

I am working on this and will try to make a pr to resolve this issue

[ayushkumar63123]

Shall I delete the whole code for p2p files not containing segwit and leave only p2p segwit files?