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
A real data format would also make re-use of the data in other projects easier. On the location service side we are collaborating with the opencellid project, and they need the exact same data. Their application is written in Java though, so a language agnostic data format would make it easier for them to parse these files.