odd characters in their names
This can result in the font falling back to a default system
font. It's notably an issue for the "ESRI Oil, Gas, & Water"
symbol font.
Eg if a font is built by calling .setBold/.setItalic and not
by QFont::setStyleName then this method will attempt to return
the equivalent style name.
Results are very platform dependent and font dependent, depending
on Qt's internal matching logic (hence no unit tests)
