WIP: Add WPTypographicSymbols support (#740)
This changeset adds a table mapping from
WPTypographicSymbols characters to their Unicode equivalents, fixing #740. It's derived from the existing
ZapfDingbats machinery and works in much the same way.
There's ongoing discussion in #740 on whether or not fixing these documents is a good idea, hence the WIP: prefix. This changeset makes
pdftotext's output useful for these documents without affecting