v0.43.0

Parser changes:

• superscript or subscript extensions only: punctuation following a superscript or subscript delimiter no longer disqualifies the delimiter from being considered left-flanking, such that e^-i^ and n~-i~ now parse as superscript or subscript respectively (by @kivikakk in #593)

Changed APIs:

• html::format_document, xml::format_document, cm::format_document and friends now take an std::fmt::Write as their output argument, instead of an std::io::Write, to avoid revalidating UTF-8 (by @kivikakk in #601)
• bin: allow --header-ids '' for prefix-less headers (by @kivikakk in #610)

New APIs:

• Add CJK Friendly Emphasis to CLI option (by @tats-u in #607)

Documentation updates:

• Introduce cargo binstall by (@tats-u in #608)
• www: add (by @kivikakk in #611)

Diff: v0.42.0...v0.43.0