use reduced alphabet for footnotes so that no footnote marker
has a descender. This is in preparation for hanging footnotes over
full-stops and commas.
fix generation of footnote marks
debug and fix some footnote list handling bugs.
update footnote marks in footnotes when reenumerating footnotes.
zero freed paragraph slot to prevent nasty bugs.
reduce debug output for footnote handling.
fix bugs with hanging verse numbers.
remove redundant hanging verse number code: now all handled in
line_recalculate_width()
hang all verse numbers at starts of lines or paragraphs.
add sample definitions for more typesetting variables.
simplify and generalise right hanging punctuation detection.