Version 3.0.0

Added initial support for outputting modern Unix manpages with -tmdoc. This is intended as a replacement for the legacy -tman. Supplement this with --roff-manpage, which accepts a markdown file that looks like a Unix manpage and attempts to convert it into a well-formed mdoc or man. Most of this is purely syntactic, but several sections in Unix manpages (e.g., the NAME and SYNOPSIS) have a rigorous syntax that this mode attempts to output.

Several minor (but breaking) changes to the API to take up fewer bits in the oflags field of struct lowdown_opts: consolidate all XXX_NOLINK, XXX_RELLINK, and XXX_SHORTLINK as LOWDOWN_NOLINK, LOWDOWN_RELLINK, and LOWDOWN_SHORTLINK. This only applies to the LOWDOWN_MAN, LOWDOWN_MS, LOWDOWN_MDOC, and LOWDOWN_TERM output modes. The earlier LOWDOWN_NROFF output mode is deprecated and is now an alias for LOWDOWN_MS, which should be used moving forward.

Do the same with the various XXX_SKIP_HTML bits.

Deprecate the lowdown_nroff_xxx in favour of lowdown_roff_xxx. The functions remain as deprecated and passing through to the new equivalents.

Deprecate the macro variables LOWDOWN_NROFF_GROFF LOWDOWN_NROFF_NUMBERED LOWDOWN_NROFF_MANPAGE LOWDOWN_NROFF_ENDNOTES in favour of their ROFF names. The old macros are aliased for compatibility.

Library bumped from version 2 to 3 for those reasons.

Tweak the behaviour of -tterm and --term-no-links (or --term-no-rellinks) with respect to embedded images and no text so that there's always a clickable link and image component, if possible.

Add --roff-no-rellinks, similar to --term-no-rellinks. Respect --roff-short-links in more cases as well.

Change the behaviour of -tms and -tman where --roff-no-links (or the new --roff-no-rellinks) will have consistent behaviour even if --roff-traditional is not specified.

Fix that, when using lowdown-diff for the terminal, resetting the colour after an insertion or delete would trigger the black colour, which obviously doesn't work with a black background. Instead, use the default colour.

When generating header identifiers in -thtml, incorporate codespan text as well. This is the same as pandoc's default behaviour as well.