Translation in Italian

The Italian translation for Discard is wrong, as Tralascia isn't a translation for it.

A better term would be Scarta (=Discard) or Non salvare (=Don't save).

I tried making a pull request on github [the pull request is here|https://github.com/qt/qttranslations/pull/7/files], but I was told to make a bug report, so here I am.

I hope I'm doing this right.