Split parts of the draw method

While poking through more of the changes made in Beeblerox's renderer overhaul branch, I noticed that the way the draw method works has changed quite a bit! Instead of a single draw() method that handles everything, two more were introduced: preDrawCheck() and drawTo(camera), with draw() being reduced to just:

override public function draw():Void
{
	if (!preDrawCheck())
		return;

	for (camera in cameras)
		drawTo(camera);
}

I think the way this was split is nice, and could make overrides less of a pain. The drawTo() method especially could be really nice if you had to force a draw on a specific camera, in the case of render textures or whatever.

Search the repository for the current draw() implementation and its renderer class, then compare how camera iteration and draw checks are handled. The issue proposes separating preDrawCheck() and drawTo(camera); done would mean the intended split is implemented without changing existing rendering behavior, with any relevant renderer tests or examples still passing.