Unify events and output single TypeScript declaration (#2407)
* fix(events): unify events to a single EventManager type, add support for single typescript declaration
* fix(lint): fix lint
* fix(events): fix incorrect instatiation
* fix(events): clean up redundant methods
* fix(events): keep EventEmitter name, alias NodeEventEmitter
* fix(events): fix loose reference
* fix(EventEmitter): remove on/off alias as redundant
* fix(RTCUtils): bring event handlers under class to use same event emitter
* fix(RTCUtils): fix lint
Daniel McAssey