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_ca_es.latin1.vim b/runtime/lang/menu_ca_es.latin1.vim
index 6e30eef..6f8ea7f 100644
--- a/runtime/lang/menu_ca_es.latin1.vim
+++ b/runtime/lang/menu_ca_es.latin1.vim
@@ -2,7 +2,7 @@
 "
 " Maintainer:	Ernest Adrogué <eadrogue@gmx.net>
 " Last Change:	26 Jul 2017
-"
+" Original translations
 
 " Quit when menu translations have already been done.
 if exists("did_menu_trans")