Allow users with no crypto to RSVP events

[makoto]

Problem

Event organisers fear that demanding people to stake is a high barrier to entry. To work it around, some event organiser use both Kickback and eventbrite/meetup.com

Possible Solutions

"Interested" feature

This is a complete off-chain feature where users can mark their interest to attend.

Facebook "Interested"

Laynyrd.com (social event tracking site, acquired by evenbrite) also had "Track" feature.

We can still store the information on our DB so that organisers can issue POAP to this list of people. However, from a Kickback point of view, these people are treated as "Not attended" to the event so no onchain history will be available to these people.
This will be a good feature to have Kickback staking while allowing people not to stake (but their entrance is not guranteed).