v4.8.1

A patch release fixing two things.

A style whose typeface was an ordinary face — Courier, for one — but whose
character-set bits said "math" printed its whole text in the Symbol font:
Greek letters instead of words, in every export. A resolved typeface now
wins; the character-set bits only decide when the typeface itself is
unknown.

Strikethrough declared by a paragraph style now stays on until a later
style turns it off, which is what WordStar 7 prints — it previously ended
with the styled paragraph. Documents whose style sheet sets strikethrough
and never clears it now print struck through to the end, as on paper. An
opt-in "quirks" mode to read such documents cleanly is planned for the next
release.

40 answer-key cells in 5 reference documents were re-recorded for these two
fixes.

Full changelog: v4.8.0...v4.8.1