ANN: pandoc 2.19.1

[John MacFarlane]

I'm pleased to announce the release of pandoc 2.19.1,
available in the usual places:

Binary packages & changelog:
https://github.com/jgm/pandoc/releases/tag/2.19.1

Source & API documentation:
http://hackage.haskell.org/package/pandoc-2.19.1

The main impetus for this release was to fix a regression
introduced in 2.19 involving link coloring on PDF output.

In addition, there is one major new feature: pandoc can now
be used as a web server or CGI program, when renamed or symlinked
as `pandoc-server` or `pandoc-server.cgi`.

As usual, there are a number of other significant improvements, which
you can read about in the changelog.

API changes:

* New exported module Text.Pandoc.Server [API change].
* Text.Pandoc.Highlighting: Export `lookupHighlightingStyle`.
* Text.Pandoc.App.Opts: The `FromJSON` instance `Opt` now
allows values to be omitted (in which case the values from
`defaultOptions` are used).
* Lua: add function `pandoc.utils.citeproc`.
* Improved https://pandoc.org/try.