Type-hinted NBT tag constructors, made getValue() and setValue() more strict, fix dozens of assorted related bugs

src/pocketmine/tile/Nameable.php

@@ -30,15 +30,15 @@ interface Nameable{
 	/**
 	 * @return string
 	 */
-	public function getName();
+	public function getName() : string;
 
 	/**
-	 * @param void $str
+	 * @param string $str
 	 */
-	public function setName($str);
+	public function setName(string $str);
 
 	/**
 	 * @return bool
 	 */
-	public function hasName();
+	public function hasName() : bool;
 }