Can't create text with PDFType1Font.ZAPF_DINGBATS or PDFType1Font.SYMBOL without installed fonts

On a system with no fonts, it is not possible to create PDF files that use the Standard 14 Symbol and Zapf Dingbats fonts. The current code tries to look at the generic fallback font (LiberationSans), which of course doesn't have these characters so an exception is thrown. But this lookup isn't needed - we have all the metrics needed for the standard 14 fonts and don't need any actual font.

Solution: change PDType1Font.encode() so that it doesn't use the generic font for standard 14 fonts.