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

[luisschwab]

Leaving as draft until v0.12.2 is released.

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

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.
• Use Amount for all value/fee fields and removed Tx::fee(),
• Replace u64 in favor of Weight on Tx and removed Tx::weight().

I'll also close #150 on this PR if we reach consensus on whether Amount should be used for all amount fields.

[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%

---

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

---

💛 - Coveralls

[oleonardolima]

cACK dbbe555