[tz] Print zdump and zic program names in --version output

[Joseph S. Myers]

On Sat, 10 Nov 2012, Robert Elz wrote:

> But why do we care about GNU standards?   Sure, POSIX, and IEEE C make
> sense to follow, but GNU??   Why??

The whole idea of --help and --version options is a GNU standard.  Given 
that those options originate in GNU standards, it makes sense to follow 
the GNU standards in what they output.

-- 
Joseph S. Myers
joseph at codesourcery.com