v2.0.0

Makes a request the only way to call a getter.

Breaking

• get_occupation(const occupation_request&) and get_occupation(request, seed); get_occupation({}) draws a random country at the default age of 40, get_occupation({.country = "US"}) fixes only the country.
• The no-argument, country-only and seed-only overloads and instance seed()/unseed() are removed. Data loading and layers stay on the instance.

See the documentation for the request type and examples.