* add a script that concatenates changelog_unreleased into a blog post draft
* syntax highlighting issues
* generate post draft
* Copy edit, remove error stacks
* Update 2020-00-00-2.0.0.md
* Update changelog source files
* edit entries, regenerate the post
* add lost file in versioned_docs
Co-authored-by: Jed Fox <git@twopointzero.us>