Europe GDPR regulation

[oitsuki]

Must be include or not ?

[maxhelias]

It's just an SDK to communicate with the MailChimp API, there is nothing to take care of

[Zauberfisch]

I agree, it's not in the project scope to have special handling for GDPR. Though some documentation is needed for how to set the marketing permissions.
I've made a start in #271, bot some extra documentation would surely be a good.