Events

_A suggestion by @SalmonDE_

The idea behind this is to call an event when MagicWE2 performs a change in the world.

With the event you should be able to:
- get the player who edited (or null when done via plugin)
- get the level where actions are performed in
- get and change which blocks were edited (Good for MWE2-Extensions #107)
- get the full selection
- change or move the selection
- Allow or restrict edits at specific positions (Useful for MyPlot!)
- limit how many blocks should be edited
- and maybe allow edits to perform asynchronous after the events were called

Any other ideas what events should be able to return / modify please below