ed: upgrade 1.18 -> 1.19

ed: upgrade 1.18 -> 1.19

Changelog:
==========
 * main_loop.c (exec_command): Fix commands 'e', 'E'; they did set
   the 'modified' flag if file not found. (Reported by Harry Graf).
   (main_loop): Print script error line to stdout instead of stderr.
 * Change long name of option '-s' to '--script'.
   (Suggested by Andrew L. Moore).
 * Assign short name '-q' to options '--quiet' and '--silent'.
 * main.c (show_strerror) Use '!quiet' to enable diagnostics.
 * Do not process file names for backslash escapes.
   (Suggested by Andrew L. Moore).
 * ed.texi: Document 0 as starting point for searches '0;/RE/'.
   Document how to achieve the effect of ex style '!' filtering.

License-Update: Copyright year updated to 2023.

Signed-off-by: Wang Mingyu <wangmy@fujitsu.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>