0.16.1

Fixed

• The corpus's own headings follow I-118. Twelve R- titles ("Frame 1:
  Minimise usability risk", the seven tiebreakers) and L-01's six steps used
  an em dash. Headings are interface text wherever they show, in explain, in
  check output and on a rendered page, so they now use a colon.
• A quotation keeps its own punctuation. I-118 now says text marked as a
  quotation with <blockquote> or <q> is the source's words, and changing
  it would misquote it; the page's own copy around it is still held to the
  rule. The render probe leaves quoted text out of its dash scan. Without
  this, a page quoting a rule verbatim could never pass its review.
• A spec's indexable: is true or false. A sentence on that line was
  read as nothing, the mode's default was used, and a correct page was
  reported as contradicting J-123. Anything else is now a spec-shape problem,
  and an error in verdicts that names the field.