Changelog for mmark-0.0.4.3

MMark 0.0.4.3

Made parsing of emphasis-like markup more flexible and forgiving, see README.md for more information.

This version uses megaparsec-6.4.0 and parser-combinators-0.4.0 and has improved performance.

Empty strings are not parsed as URIs anymore (even though a valid URI may be represented as the empty string). Instead, it's now possible to write an empty URI using the <> syntax (which previously was not recognized as a URI in some contexts).
Improved parse errors related to parsing of titles in links, images, and reference definitions.
Parsing of reference definitions now can recover from failures, so the parser doesn't choke on malformed reference definitions anymore.
Reduced allocations and improved speed of the parser significantly.

Fixed a couple of bugs in the parser for reference definitions.
Now link and image titles may contain newline character as per the Common Mark spec.

Code can interrupt paragraphs now, as per Common Mark spec.
Implemented parsing of reference-links (including collapsed and shortcut-style links).
Implemented parsing of reference-style images (including collapsed and shortcut-style images).
Added support for entity and numeric references (section 6.2 of the Common Mark spec).
Improved quality of parse errors.

Improved performance of the parser. Mainly the inline-level parser to be precise. The result is that now there are 3× less allocations and the code runs about 3× faster on paragraphs and block quotes (it's about 2.5× faster for a big realistic document).
Improved quality of parse errors.

Fixed a bug in skipping of headers (only one newline after the header line was picked, not all white space up to next block).