In any language where the str2url would return an empty string. The behavior
doesn't change for european characters.
rvelices warned me about the many issues we might encounter with copy/paste of
the URL and required url_encode/url_decode BUT after many tests (Linux with
Firefox 3.0/Google Chrome 5, MacOS 10.6 with Firefox/Safari, WindowsXP with
IE6/Firefox) I've found 0 problem, even with the most error prone mode
$conf['tag_url_style'] = 'tag'
git-svn-id: http://piwigo.org/svn/trunk@6060 68402e56-0260-453c-a942-63ccdbb3a9ee
0ce0f28a23