Merged r11919 from trunk to 2.3-stable (#14196)

Italian translation for 2.3-stable by Riccardo Rocca.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/branches/2.3-stable@11922 e93f8b46-1217-0410-a6f0-8f06a7374b81