Add support for the Batak script (bug #55694)

Add support for the Batak script (bug #55694)

* lisp/language/indonesian.el ("Batak"): New language environment.
Add composition rules for Batak.  Add sample text and input
method.
* lisp/international/fontset.el (script-representative-chars)
(setup-default-fontset): Support Batak.
* lisp/leim/quail/indonesian.el ("batak"): New input method.
Rename TITLE of balinese, javanese and sundanese in
("quail-define-package").

* etc/HELLO: Add a Batak greeting.
* etc/NEWS: Announce the new language environment and its
input method.