Investigate new event management Admin API

[mkurapov]

Instead of using eventId in order to add/withdraw/deposit liquidity, we should consider using outgoingPaymentId and incomingPaymentId to move around liquidity.

[mkurapov]

CC @sabineschaller

[sabineschaller]

Yes, I agree. Event based always seemed weird to me. Do we then still need the view of all events?

[mkurapov]

@sabineschaller reposting my response in #1503:

We still would like the option to be able to view all of the different events that have been sent. The issue #1521 above is more concerned with how and by which parameter we want to track liquidity movement.