Release 6.0.0 - Githubissues

Improve compatibility with Markdown standards
Completely refactor plugin and preset API
Move built-in plugins and default preset into separate packages
Add tests for all official plugins and presets
Change reference numbering for anchor and image tags to a one-based index
Rename anchor tag referencing from anchorN to linkN
Simplify reference management for plugins
Refactor options API to ensure immutability
Move plugin-specific text conversion and escape logic to plugins
Refactor internal environment management for Europa Core implementations and introduce DOM wrappers
Create europa-worker package to allow usage of Europa within a service/web worker
Add eol option to override the environment-specific end of line character
Create europa-build package to simplify generation and maintenance of plugin/preset packages
Include comments in generated TypeScript declaration files
Fix build status shields
node-europa: Replace jsdom with cheerio
node-europa: Move CLI into a new europa-cli package

neocotic / europa