Fix opening epub files with non ascii names on Windows
epub_open wants an utf8 in Windows
It probably also wants utf8 in Linux, but the qPrintable already gives us an utf8 in most of the normal Linux locales, so don't touch that
epub_open wants an utf8 in Windows
It probably also wants utf8 in Linux, but the qPrintable already gives us an utf8 in most of the normal Linux locales, so don't touch that