Level: Change isInWorld signature to use ints instead of floats

this is only used in one place, where it's being given floats, and it's 10% faster to use int for this because it won't convert it.

It is also 25% faster to remove typehints and 60% faster to inline it. We really need a proper PHP preprocessor for inlining.

src/pocketmine/level/SimpleChunkManager.php

@@ -172,7 +172,7 @@ class SimpleChunkManager implements ChunkManager{
 		return $this->worldHeight;
 	}
 
-	public function isInWorld(float $x, float $y, float $z) : bool{
+	public function isInWorld(int $x, int $y, int $z) : bool{
 		return (
 			$x <= INT32_MAX and $x >= INT32_MIN and
 			$y < $this->worldHeight and $y >= 0 and