Represents a bitcoin payment URI. Bitcoin URI strings became the most popular way to share payment request, sometimes as a bitcoin link and others using a QR code.
The main use that we expect you'll have for the `URI` class in bitcore is validating and parsing bitcoin URIs. A `URI` instance exposes the address as a bitcore `Address` object and the amount in Satoshis, if present.
All standard parameters can be found as members of the `URI` instance. However a bitcoin URI may contain other non-standard parameters, all those can be found under the `extra` namespace.
Another important use case for the `URI` class is creating a bitcoin URI for sharing a payment request. That can be accomplished by using a dictionary to create an instance of URI.