Brand Store - Give more options for e-mail templates

How: Give more options for email templates in the Brand Store Admin.

Why: Help users personalize the Brand Store to their company's needs.

Additional context:

The new Brand Store Admin/Configurator gives the option to create templates for certain emails sent by the Brand Store. As of now it is only possible to configure the email sent for downloading content from the Brand Store.

It would be great if it would be possible to configure other emails as well. E.Gg. the emails sent for a new user sign up (invitation to the Brand Store) and also for the mail to change your password.

This would help users to configure the Brand Store according to their company guidlines.