3.0.0-alpha

Development:

• Comply with CommonMark 0.30. (contributed by @lostenderman, #29, #210, #212, #226)
• Add a demo of using the Markdown package in OpTeX. (contributed by @olsak, #215, 109c1b5, #292)
• Add singletonCache Lua option. (#226)

Documentation:

• Add @lostenderman's thesis to README.md. (#226, 8a4536e)

Default Renderer Prototypes:

• Do not force line breaks after headings in LaTeX. (df8562c)

Deprecation:

• Remove deprecated parts of the package. (#309)
• Remove support for LuaMetaTeX. (#226)

Fixes:

• Allow references in fenced divs. (#307, jgm#69)
• Prevent eagerCache=false from causing undefined behavior and make it the new default. (#129)