Add a new chapter on speakers, relation and membrane about training HOT 1 OPEN

We tried to implement this but ran into a couple of issues that led us to table that for now

Mostly, self-registration does not work well with membrane . A approach was to open ++add++speaker upon registration. That would require:

• Add a folder where anonymous has the permissions Add portal content and Add speaker (via a placeful workflow or manage_access or a bustom type with a custom workflow)
• Change the link to register-action link to /Members/++add++speaker or similar

The problem with this are:

• Registration looks like a normal add-form and not like a registration-form. Could be solved by Custom form title and using a redirect after adding with immediate_view.
• The user is not forced to confirm the registration by mail
• Speaker cannot change his setting. Solution would be to ping the action personal-preferences to the edit-form of the current speaker
• Password is no required field in IProvidePasswordsSchema. Could be solved by overriding the schema

Alternatives:

• Add Membrane-Speaker with subscriber after self-registration
• Use default MemberdataSchema

from training.