Ordering across publishers

[somdoron]

I think we can achieve semi-ordering across producers using Hybrid Logical Clocks, semi because:

1. In real-time the events will be ordered by the time they arrive at the consumer (but always ordered per producer).
2. When synchronizing with history the events would be ordered by the timestamp assigned by each producer - so always order per producer and very close to the order of real-time.

The store should now save the events by topic and timestamp

https://bartoszsypytkowski.com/hybrid-logical-clocks/