Provide a proper OOP-way to handle events in Class API

[Raiondesu]

Is your feature request related to a problem? Please describe.
While #42 introduced a solid way to handle events in an OOP-style, it's still not a 1-to-1 mapping of all Eventhoven functionality.
Currently, these things are missing from the implementation:

• Ability to add or remove events from the map, as it is possible via the eventMap function;
• Ability to properly implement inheritance patterns in order to modify current behaviour of events.