output version info similar to other unix commands

[jerry57]

Would be nice/useful if jsawk would output its version info similar to other unix commandline utilities "jsawk -v" or "jsawk --version"

ie: diff --version diff (GNU diffutils) 2.8.1 Copyright (C) 2002 Free Software Foundation, Inc.

This program comes with NO WARRANTY, to the extent permitted by law. You may redistribute copies of this program under the terms of the GNU General Public License. For more information about these matters, see the file named COPYING.

Written by Paul Eggert, Mike Haertel, David Hayes, Richard Stallman, and Len Tower.

[micha]

Good idea. I'll get it into the next release.