Cannot access struct properties

[rviljoen]

Thanks for pulling this project together! I was able to run the tests successfully, but when I add it as a package on a new project and try to access the struct properties I get the following error (as an example):

cities is inaccessible due to 'internal' protection level

If I edit the package to make the property public, it works, e.g.:

public let cities: Cities

I'm not sure if I'm adding the package incorrectly, or if you need to update all the properties to public. Thought I'd mention it here.