Dummy moat distributor

Implement a dummy moat distributor to distribute the censorship map (bridgedb#40025 (closed)).

It requires three API endpoints:

• Get Circunvention Map. Provide the static json file with the list of countries.
• Get circunvention settings. Use the IP of the client (or a provided param) to return the right settings for the country.
• Get BuiltIn bridges.

As long as #12 (closed) is not ready we'll provide dummy bridges in the circunvention map to test that everything works properly.