chore(api)!: remove BlockSummary and PrevOut, rename scripthash_txs to get_scripthash_txs

[luisschwab]

Closes #142.
Closes #146.
Closes #148.
Closes #150.

This PR:

• Removes BlockSummary and uses BlockInfo for get_blocks, as BlockSummary fails to capture the full response,
• Removes PrevOut, which is identical to Vout,
• Renames scripthash_txs to get_scripthash_txs, to maintain the method naming convention.
• Uses Amount for all value/fee fields and removed Tx::fee(),
• Replaces u64 in favor of Weight on Tx and removed Tx::weight().

[coveralls]

Pull Request Test Coverage Report for Build 20796560586

Details

• 21 of 22 (95.45%) changed or added relevant lines in 4 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.008%) to 86.658%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/api.rs	1	2	50.0%

Totals
Change from base Build 20725239190:	0.008%
Covered Lines:	1403
Relevant Lines:	1619

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💛 - Coveralls

[oleonardolima]

cACK dbbe555

[oleonardolima]

utACK eccf30d

I'm also wondering on how disruptive it'll be on downstream, see VM's comment, though it'll be in a major release.

[luisschwab]

I don't think this is a very disruptive API break, especially since the response type is just plain wrong right now.