Rewrite parser for iv-org/documentation#76

[syeopite]

This PR rewrites the parser to account for iv-org/documentation#76.

All new fields added by said PR has been added as well.

This PR also contains the code from #29.

[B0pol]

I wouldn’t introduce breaking change for such a small thing. Just add a new field

[syeopite]

Considering this basically rewrites the entire parser I wouldn't exactly consider this PR to be a small change.

[B0pol]

I’m talking about the "country" object. Why don’t you add a new field instead of adding a breaking change and moving two fields?

[syeopite]

Fair enough. I've went ahead and unnested it along with the modified object in order to reflect iv-org/documentation#76