Add g0v.json

[kcwu]

If this project does not belong to http://g0v.tw/ or is not applicable,
you can ignore and close this bug.

Otherwise please add g0v.json to your project.
See https://g0v.hackpad.com/g0v.json-spec-c07sSfauWSc for detail.

You can see the progress of adding g0v.json here: g0v/hack.g0v.tw#35