Outer divs have longer fences. This aids clarity for the reader,
making it easier to see where the div ends. It also makes the
output compatible with some other implementations, e.g.
micromark, which require different-width fences for nesting.
Closes#9450.
According to the CSL manual, the default entry spacing is 1.
We were treating it as 0.
T.P.Citeproc: always include an entry-spacing attribute
in the Div if the bibliography element contains an entry-spacing
attribute (previously we omitted it when it was 0).
LaTeX writer: use entry spacing 1 if no entry-spacing
attribute is present.
Update tests.
See #9058.
Previously we used Setext (underlined) headings by default.
The default is now ATX (`##` style).
* Add the `--markdown-headings=atx|setext` option.
* Deprecate `--atx-headers`.
* Add constructor 'ATXHeadingInLHS` constructor to `LogMessage` [API change].
* Support `markdown-headings` in defaults files.
* Document new options in MANUAL.
Closes#6662.
John MacFarlane