Replace BlockFromToEvent with Block(Liquid?)FlowEvent and BlockTeleportEvent

[xt449]

Is your feature request related to a problem?

No; however, due to the naming of this event it can be difficult for new users of the API to find this event when wanting to handle liquid flowing, or dragon egg teleportation.

Describe the solution you'd like.

Deprecate BlockFromToEvent and create two other more distinct events.
Possible names are LiquidFlowEvent or BlockFlowEvent, and BlockTeleportEvent.

Describe alternatives you've considered.

N/A

Other

The BlockFromToEvent has two very different possible sources that can call it.