Decouple volunteer registration from conference registration

[andreasscherbaum]

Having volunteers tied to a registration is challenging:

• There is the multi-step signup which always needs explanations: "1: sign up for the conference", "2: let us know", "3: we add you as volunteer", "4: pick volunteer slots". This creates friction.
• For FOSDEM we have multiple volunteers who are not coming to the PGDay, and still need a registration for volunteering over the weekend.
• If a volunteer signs up for helping at FOSDEM and the registration is closed (because PGDay on Friday is over), we need to open the registration again.
• We have volunteers who are not on-site, and don't have a reg.

If the volunteering is not tied to a registration, it makes it easier for a conference manager to just add volunteers without keeping track for if and when they have a reg.

[andreasscherbaum]

Add: for "FOSDEM Weekend Staff" registration there is no email and no notification that a registration must be manually confirmed. The volunteer needs to reach out and let the conference know that they signed up. This is even more friction if people decide to help.