patch 8.2.4420: menu translations are inconsistent

Problem:    Menu translations are inconsistent.
Solution:   Add a Makefile to convert between encodings. (Ada (Haowen) Yu,
            closes #9801)
diff --git a/runtime/lang/menu_it_it.latin1.vim b/runtime/lang/menu_it_it.latin1.vim
index 927c3c9..9ce8b87 100644
--- a/runtime/lang/menu_it_it.latin1.vim
+++ b/runtime/lang/menu_it_it.latin1.vim
@@ -3,6 +3,7 @@
 "			Vlad Sandrini <vlad.gently@gmail.com>
 "			Luciano Montanaro <mikelima@cirulla.net>
 " Last Change:	2020 Apr 23
+" Original translations
 
 " Quit when menu translations have already been done.
 if exists("did_menu_trans")