(Finsert_file_contents): Update call to CHAR_HEAD_P.

(Finsert_file_contents): Update call to CHAR_HEAD_P.

(Fwrite_region): Use scan_newline.

(restore_point_unwind): Now static.  Use Fgoto_char.
(Funhandled_file_name_directory): Doc fix.
(Finsert_file_contents): Handle bytes vs chars.
(Fwrite_region): Handle bytes vs chars.
(a_write): Take args in bytes; handle annotations labeled in chars.
(e_write): Rename args.
(Funhandled_file_name_directory): Doc fix.
(a_write, e_write): Now static.