Remove <string> includes in headers

include/godot_cpp/core/class_db.hpp

@@ -47,7 +47,6 @@
 #include <list>
 #include <mutex>
 #include <set>
-#include <string>
 #include <unordered_map>
 #include <vector>
 

include/godot_cpp/core/method_bind.hpp

@@ -39,11 +39,8 @@
 
 #include <godot_cpp/classes/global_constants.hpp>
 
-#include <string>
 #include <vector>
 
-#include <iostream>
-
 namespace godot {
 
 class MethodBind {

src/godot.cpp

@@ -39,6 +39,8 @@
 
 #include <godot_cpp/core/error_macros.hpp>
 
+#include <stdio.h>
+
 namespace godot {
 
 namespace internal {