[Yhc] Yhc Version number

[Neil Mitchell]

Hi Robert,

> Perhaps the timestamp on the most recent patch would be better than the number
> of patches.  It looks like you can get that pretty easily
> from 'darcs/inventory'.

We did consider that, but we were worried that versions would end up
being too long, plus there is a risk that people will have the wrong
date on their computer. If the patch count can't be done easily then
thats probably the best thing to do.

Thanks

Neil