Digitz

Major API changes.
- Only a single `PhoneNumber` class is available. (SlottedPhoneNumber, PhoneNumberTuple, and FrozenPhoneNumber have been removed)
- This class is a frozen dataclass.
- Many new properties are available on the PhoneNumber class including
- national_destination_code
- subscriber_number
- is_geographical
- is_voip
- is_exact_match
- Added replace() method that returns a new PhoneNumber object with the replaced fields. (Similar to datetime objects)

- Added additional documentation.
- Documentation can be found at https://digitz.rykroon.com
- PhoneNumber object uses slots.

* Added parse() function that returns a PhoneNumberTuple instance.
* Added CountryCodeSource Enum.
* PhoneNumber objects are frozen.

Say Hello to Digitz! A Developer friendly wrapper around the `phonenumbers` library.