[eCash dev libraries] [p13 ecash-ops] ecash dependencies all the way down

Summary:
T2847

Depends on D12869

Replace legacy dependencies used in ecashjs-lib with now-published ecash specific dependencies

Test Plan: Review CHANGELOG.md and confirm described changes match changes to package.json

Reviewers: #bitcoin_abc, emack

Reviewed By: #bitcoin_abc, emack

Differential Revision: https://reviews.bitcoinabc.org/D12870