Add metadata when creating a pdf file

Provide a method on QPdfWriter that allows embedding xmp metadata in the generated pdf.

a method such as setXmpMetadata(byte[] xmpMetadata) in ittext 7 would be sufficient

https://api.itextpdf.com/iText7/java/7.0.0/

that would allow the user of the method to create the metadata using the xmp toolkit, Qt's own QXMLStreamWriter or other methods.