Move data to json (#15)

- Move hard coded countries and operators into json files
- Parse files at init time
- Update all handlers to expect unicode/lists
- Update tests
In fact, in the parse script:

https://github.com/andymckay/mobile-codes/blob/master/parse.py#L17

There is an arbitrary amount of 'significant' white space embedded in the output statement, which means if we were to make any changes to the python code that that's meant to live inside of, it would break this parser.  This is why writing scripts that use string formatting to generate python code are bad.  Just write it to a data format, that's why serializer/deserializers exist.