Support for the web window.requestAnimationFrame() support in EmuKit

Description

The current web solution for controlling the emulation execution is focused on the usage of the setTimeout().

This solution provides inaccurate results and erroneously distributes the work over time.

We should experiment with an alternative (configurable) strategy that is synced with the Display (V-Sync) using the requestAnimationFrame() function.

EmuKit should be updated accordingly to allow this control flow.

The update should include moving part of the general game loop control logic into Emukit.

References

• https://developer.mozilla.org/en-US/docs/Web/API/window/requestAnimationFrame
• https://stackoverflow.com/questions/19764018/controlling-fps-with-requestanimationframe