Add waste metric for coin selection

Co-authored-by: csralvall <[email protected]>
Co-authored-by: afilini <[email protected]>

Author: 3 people

CHANGELOG.md

@@ -6,8 +6,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-- added `OldestFirstCoinSelection` impl to `CoinSelectionAlgorithm`
+- Added `OldestFirstCoinSelection` impl to `CoinSelectionAlgorithm`
 - New MSRV set to `1.56`
+- Added `Waste` struct to `coinselection` module, with impl of
+  `Waste::calculate` to compute waste metric for coin selection algorithms.
+- Added `_cost_of_change` parameter for `CoinSelectionAlgorithm::coin_select`
+  to pass the cost of generating change to calculate the waste metric for each
+  algorithm.
+- Changed `OutputGroup` owned `weighted_utxo` value to borrowed one.
 
 
 ## [v0.18.0] - [v0.17.0]