Reorganized core/ directory, it was too fatty already

-Removed FuncRef, since Callable makes it obsolete
-Removed int_types.h as its obsolete in c++11+
-Changed color names code

modules/visual_script/visual_script_editor.cpp

@@ -30,11 +30,11 @@
 
 #include "visual_script_editor.h"
 
-#include "core/class_db.h"
 #include "core/input/input.h"
+#include "core/object/class_db.h"
+#include "core/object/script_language.h"
 #include "core/os/keyboard.h"
-#include "core/script_language.h"
-#include "core/variant.h"
+#include "core/variant/variant.h"
 #include "editor/editor_node.h"
 #include "editor/editor_resource_preview.h"
 #include "editor/editor_scale.h"