* updated coinbase nuget url.
update nuget packages
Refund order to wallet in currency
Refund readme example
AAA comments on test
Merge branch 'master' of https://github.com/ryanmwilliams/Coinbase
refactor cents/currency object
* Removing TotalNative for existing Price object
* Removing RefundTransaciton for existing Transaction model
* Refactored API with better usage semantics RefundOptions
* Added support for "mispayment" refunds
* Refactoring with existing domain model
* Merging #5 to master with some refinements.