[t2t] SVN release number in txt2tags version

[Aurélio Jargas]

Hi there!

Just a quick note for those who use the SVN version of txt2tags (I do!).

Now the SVN release number is appended to the txt2tags version:

$ txt2tags -V
txt2tags version 2.6.395 <http://txt2tags.org>

$ tail -n 3 web/index.html
<!-- html code generated by txt2tags 2.6.395 (http://txt2tags.org) -->
<!-- cmdline: txt2tags web/index.t2t -->
</BODY></HTML>

So now you know exactly which txt2tags version generated that document.

The stable release will continue to be major.minor: 2.6, 2.7, 2.8, etc