Aborting callOnEachEvent

[palaga]

Currently, a call to callOnEachEvent can't be aborted. If some higher level logic is restarted, a new event loop will be created, but an old one cannot be cleaned up (i.e. aborted).

My use case is a custom node in node-red. A redeploy of the node causes a new event loop to be spawned.

A solution could be to let callOnEachEvent return an object that can be aborted.