bugfix; hashbang cmds always ok; fix '-c'
bugfix; hashbang cmds always ok; fix '-c'

bin/modernish:
- _Msh_tmp_doHashbangPreload(): Fix bug introduced by ed6d7463: whitespace
  trimming was handled incorrectly for hashbang comment commands.
- Now parse hashbang comment commands for scripts sourced from
  standard input or 'modernish -c "$script"', so ksh93 can use aliases
  from modules even in those situations.
- Further fix 'modernish -c "$script"': this now acts like shells do,
  passing on the PPs. The only limitation is we can't set $0 to the first
  argument following the script (it is not possible in POSIX to change $0 in
  shell script), so set $ME instead. This limitation is shared with the
  '#!/usr/bin/env modernish' hashbang path for modernish scripts.

modernish/modernish