Subscribe form works as an e-mail newsletter.
To activate such form with an enabled MailChimp service, replace the
.rd-mailform class with .mailchimp-mailform and the form's action
with MailChimp
subscription URL.
To activate the Campaign Monitor service, you need to replace the form’s
[#code.rd-mailform] class with .campaign-mailform and copy the form's action
and the name of
the input field from the form generated
by Campaign Monitor service.
