A simple change done according to https://www.kernel.org/pub/software/scm/git/docs/git-check-ref-format.html.
Rewriting systematically every '.' was unneeded, as only '..' is forbidden, and '.' appear very often in tag
names (eg, TAG 1.0).
1 patch for repository http://darcs.net:
patch b698289e1d414f9ddfc235881b853509030d1500
Author: Guillaume Hoffmann <guillaumh@gmail.com>
Date: Fri Mar 20 17:38:32 ART 2015
* fast-export: rewriting single dots in tags was unneeded