Removed @deprecated classes, methods and properties, added some type hints

src/pocketmine/level/Position.php

@@ -67,30 +67,6 @@ class Position extends Vector3{
 		return $this->level !== null;
 	}
 
-	/**
-	 * Marks the level reference as strong so it won't be collected
-	 * by the garbage collector.
-	 *
-	 * @deprecated
-	 *
-	 * @return bool
-	 */
-	public function setStrong(){
-		return false;
-	}
-
-	/**
-	 * Marks the level reference as weak so it won't have effect against
-	 * the garbage collector decision.
-	 *
-	 * @deprecated
-	 *
-	 * @return bool
-	 */
-	public function setWeak(){
-		return false;
-	}
-
 	/**
 	 * Returns a side Vector
 	 *