- Add definition lists, marked up like this:

	-- | This is a definition list:
	--
	--   [@foo@] The description of @foo@.
	--
	--   [@bar@] The description of @bar@.

  Cunningly, the [] characters are not treated specially unless a [ is
  found at the beginning of a paragraph, in which case the ] becomes
  special in the following text.


- Add --use-contents and --gen-contents, along the lines of
  --use-index and --gen-index added yesterday.  Now we can generate a
  combined index and contents for the whole of the hierarchical
  libraries, and in theory the index/contents on the system could
  be updated as new packages are added.