Add Miniscript max_weight_to_satisfty

[yancyribbens]

Use miniscript's max_weight_to_satisfy() method to calculate the max satisfaction weight instead. Currently, implementers of this crate are required to loop through each UTXO and calculate the satisfaction_weight. Instead, by using max_weight_to_satisfy() should allow the implementer to pass the UTXO set unmodified.