Fix listener leak for timers/promises

[WhiteAutumn]

Purpose (TL;DR)

Fix abort event listener leak discussed in #495 by adding abortListenerMap to keep track of active abort listeners.

Solution

The leak is fixed by adding a map with listener functions as keys and the abort signals as values. During uninstall it iterates over the map and removes the listeners. If a timer is aborted or finishes on its own the listener signal pair will be removed from the map.

[fatso83]

Great addition. Both this and the previous PR is very nice work! Thanks a lot!