[FYI] Apipie documentation strings marked for translation

I'd like to inform that the apipie documentation strings in both the
Foreman and the Katello projects are marked for translation. It is
needed for localized Hammer CLI and API documentation.

Katello has the PR already merged
[https://github.com/Katello/katello/pull/4063] and in Foreman it is in
progress [https://github.com/theforeman/foreman/pull/1428].

When you are changing the API docs, make sure the descriptions for api
methods and params are wrapped with N_(). The N_ marks the string for
translation, but does not translate on load as we need to trigger the
translation later.