Regularize the help output of programs.

Only print to the standard output, and only give the version
information, if a "print help" command-line option is specified.
Otherwise, leave out the version information, and print to the standard
error.

Leave out the copyright information; it's extra cruft, and

	http://www.gnu.org/prep/standards/html_node/_002d_002dhelp.html

doesn't say anything about it (and bash, at least, doesn't print it).

Change-Id: Ic5029ccf96e096453f3bd38383cc2dd355542e8a
Reviewed-on: https://code.wireshark.org/review/2789
Reviewed-by: Guy Harris <guy@alum.mit.edu>