Merge #12240: [rpc] Introduced a new fees structure that aggregates all sub-field fee types denominated in BCH

Summary:
7de1de7 Add new fee structure with all sub-fields denominated in BTC (mryandao)

Pull request description:

the denomination for `fee` is current in btc while the other such as `decendentFee` and `ancestorFee` are in satoshis.

Tree-SHA512: e428f6dca1d339f89ab73e38ce5903f5465c46b159069d9bcc3f8b1140fe6657fa49a11abe0088e9f7ba9999f64af72a349a4735bf5eaa61b8e4a185b23543f3

Backport of Core PR12240
https://github.com/bitcoin/bitcoin/pull/12240/

Also included PR13109 and PR13124 (small typo fixes)
https://github.com/bitcoin/bitcoin/pull/13109/
https://github.com/bitcoin/bitcoin/pull/13124/

Test Plan:

make check
test_runner.py

Reviewers: deadalnix, Fabien, jasonbcox, O1 Bitcoin ABC, #bitcoin_abc

Reviewed By: jasonbcox, O1 Bitcoin ABC, #bitcoin_abc

Differential Revision: https://reviews.bitcoinabc.org/D4151