* Add a Printers::allPrintersWithPdf option which includes a fake pdf at the bottom * Add a PrinterInfoAllImpl which combines PrinterInfoPdfImpl and PrinterInfoImpl for listing * Add a PrinterInfoPdfImpl which implements a fake pdf printer (just a name in the list) * Add isPdf role to PrinterModel * Add filterOnPdf to PrinterModel to allow for only showing pdf printers * Force pdf printers to bottom of the PrinterModel * Inject a fake ColorModel in PrinterPrivate::loadColorModel for pdf printers * Change PrinterJob::setPrinterName to use PrinterInfoAllImpl for retreiving the PrinterInfo * Improve the UI names for the Duplex modes * Improve detection of color models so that "black" is a greyscale type * In the example disable duplex mode when there is only None * Fix colorModelType not emitting when it may have changed, causing QML to get out of sync