Migrate Transaction to pro-macros

[ItoroD]

Description

This PR migrates Transaction to pro-macros

Notes to the reviewers

• Policy link is broken in fn vsize(&self) see main doc [here ]. So I took that part out of the doc here (https://docs.rs/bitcoin/latest/bitcoin/struct.Transaction.html#method.vsize)
• I am not sure if this is the right api docs for serialize(&self) here
• I wondering if we need to put a doc for the default constructor.

Checklists

All Submissions:

• I've signed all my commits
• I followed the contribution guidelines
• I ran cargo fmt and cargo clippy before committing

New Features:

• I've added docs for the new feature

[thunderbiscuit]

Awesome stuff!

To answer your questions:

1. Not sure what the Policy link is. Can you elaborate? But right now your vsize doc looks good to me!
2. For serialize, I would instead use

/// Serialize transaction into consensus-valid format. See https://docs.rs/bitcoin/latest/bitcoin/struct.Transaction.html#serialization-notes for more notes on transaction serialization.

3. I think it makes sense to have docs for the main constructor.

[ItoroD]

Awesome stuff!

To answer your questions:

1. Not sure what the Policy link is. Can you elaborate? But right now your vsize doc looks good to me!

Thanks for the feedback!

There is a hyperlink that says policy in the doc for vsize here. That link is broken. So I took it out in this PR.

[thunderbiscuit]

Oh I see! Perfect yep.

[thunderbiscuit]

ACK d069771.