Updated Slovenian translation
https://bugs.webkit.org/show_bug.cgi?id=113151

Patch by Matej Urbančič <mateju@svn.gnome.org> on 2013-03-27
Reviewed by Gustavo Noronha Silva (kov).

* sl.po: translation update.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@147003 268f45cc-cd09-0410-ab3c-d52691b4dbfc