Halibut reads documentation source in a single input format, and produces
multiple output formats containing the same text.
The supported output formats are:
* Plain ASCII text
* HTML
* PDF
* PostScript
* Unix man pages
* Unix info, generated directly as .info files rather than .texi sources
* Windows HTML Help (.CHM files), or rather source which can be fed to
the MS HTML Help compiler to generate them
* Windows WinHelp (old-style .HLP files), generated directly without
needing a help compiler.