Fixed some trailing whitespace

$ shopt -s globstar
 $ sed -i 's/[ \t]*$//' src/pocketmine/*/**.php

:P

src/pocketmine/level/Position.php

@@ -50,13 +50,13 @@ class Position extends Vector3{
 
 	/**
 	 * Return a Position instance
-	 * 
+	 *
 	 * @return Position
 	 */
 	public function asPosition() : Position{
 		return new Position($this->x, $this->y, $this->z, $this->level);
 	}
-	
+
 	/**
 	 * Returns the target Level, or null if the target is not valid.
 	 * If a reference exists to a Level which is closed, the reference will be destroyed and null will be returned.