Updating duo-parse to allow semver deps

I've updated to `duo-parse@0.2.0` here, which unfortunately broke the tests due to an [undocumented/untested export](https://github.com/duojs/parse/blob/0.1.1/index.js#L16) that wasn't accounted for in the recent refactor. (but that's good, because it was pretty tightly coupled and I don't think belonged there anyways)

Also, one of the examples had a weird slug (`yields/shortcuts/index`) that broke the test, and I don't believe we want to support that syntax, so I've just changed it. (correct me if I'm wrong)

This will fix #385, and I've even added a test to make sure of that. :)