Bug#811565: [uscan] git mode: allow for scanning repositories without tags

[Osamu Aoki]

Hi,

On Fri, Aug 11, 2017 at 08:09:39PM +0200, Michael Stapelberg wrote:
> Ah, thanks for the correction. In that case, we should probably try a shallow
> clone first, then fall back to a non-shallow clone :).

That's my plan.  The same thing can be said for existing git archive
command.  So I am refactoring code too.

Osamu