Assegnate 4 su 5 stelle

Maybe it doesn't work for Japanese users these days.
It causes by breaking Japanese language file, so I fix it.

Here is Japanese compatible version.
http://knoa.jp/up/imagetweak.0.23.ja.xpi

Detail of this problem is here:
https://github.com/CAFxX/ImageTweak/issues/18

Questa recensione riguarda una versione precedente (0.23.1-signed.1-signed) del componente aggiuntivo.