[icedtea-web][rfc] Localized about messages

[Jacob Wisor]

Hello,

since refactoring the about dialog has added new messages, I hereby provide localized DE and PL messages.

The message RCantBackup has been added to accomodate an error message for handling backup errors on filesystems that do not allow overwrite on rename. Unfortunatelly, I do not recall the status on that. Jiri, maybe you know more? Apart from that it sould be fine.

Regards,
Jacob