This diff adds a TestJob and associated action in Part. Test functionality is enabled in plugin json files, currently for clizip, clirar and cli7z. Test results are displayed simple as success/failure in a KMessageBox.
We can work on a more elaborate UI showing files that failed etc. in a separate patch.
Testing password-protected archives will currently result in an errorbox, due to these archives potentially having different passwords for each file and hence multiple password prompts might pop up.
Bug 140492 (reported in 2007!!)