backwards compat breaking gamejs event & tick changes will soon be merged

[Simon Oberhammer]

I created a `implicit-eventloop` branch, which will soon be merged into main and will also get a release soon.

**This will break all games (but it should be a relatively easy fix)**

What changed? This example shows it quiet well: (notice `gamejs.onEvent` and `gamejs.onTick`):

https://github.com/oberhamsi/gamejs/blob/implicit-eventloop/examples/event/javascript/main.js

This is a more natural and direct mapping of the event and "game loop" model we get in JavaScript; it also removes much unnecessary and complicated code from gamejs.

More details on this change can be found in this commit: https://github.com/oberhamsi/gamejs/commit/4624296a8995ded0a625018769566b1f1a440efe

I'm still fleshing out bugs and updating the docs but I'm hoping to get this out the door soon.

  simon