hashbang preload: suppress "read: Illegal byte sequence" in yash
hashbang preload: suppress "read: Illegal byte sequence" in yash

bin/modernish:

- Sometimes, if there is no script, $0 (hence $ME) is the shell
  binary itself, such as in the case of: yash -c '. modernish;
  some commands here'
  The _Msh_tmp_doHashbangPreload function uses the "read" builtin
  to try to read hashbang commands from $ME, aborting if any line
  is encountered that does not start with '#!'. This should be safe
  enough to avoid parsing binary executables.
  However, yash's "read" builtin does not like non-text (non-UTF-8)
  sequences, such as in binary executables, and prints a message to
  standard error:
    read: cannot read input: Illegal byte sequence
  This is harmless, but ugly. This commit redirects standard error
  to /dev/null to avoid it.

modernish/modernish