Thomas Arendsen Hein <thomas@intevation.de> [Thu, 04 Oct 2012 16:52:20 +0200] rev 17707
subrepo, hghave: use "svn --version --quiet" to determine version number
svn --version --quiet is implemented since svn 0.14.1 (August 2002)
and prints just the version number, not the long output (21 lines)
of "svn --version".
Additionally I expect this output format to be more stable, at least
it is not changed with different translations.