ANN: pandoc 2.16.2

[John MacFarlane]

I'm pleased to announce the release of pandoc 2.16.2,
available in the usual places:

Binary packages & changelog:
https://github.com/jgm/pandoc/releases/tag/2.16.2

Source & API documentation:
http://hackage.haskell.org/package/pandoc-2.16.2

This release adds an exciting new feature: it is now possible
to create custom readers (parsers) in Lua, to support formats
not currently understood by pandoc. Custom writers were already
possible, as were custom AST transformations (filters). So now
every step in the conversion process can be customized using Lua.

To facilitate custom readers (and for use in filters), we
now compile lpeg into the Lua subsystem. lpeg is a library
allowing easy construction of parsers using a PEG grammar.
Filters and custom readers can use lpeg without assuming
that the users have it installed locally.

For more on custom readers, see the documentation at
<https://pandoc.org/custom-readers.html>.
This includes three examples, including a RIS bibliography
parser and a parser for WikiCreole syntax (only 190 lines
of Lua, and it performs better than the built-in creole reader).

In addition to this major feature, this release contains a
number of smaller bug fixes and minor improvements.

API change:

- New module Text.Pandoc.Readers.Custom, exporting readCustom.

Thanks to everyone who contributed, including Albert Krewinkel,
Aner Lucero, Christophe Dervieux, and new contributors
Christian Despres, Rowan Rodrik van der Molen, Fabián Heredia Montiel,
S.P.H, and willj-dev.