5.0.0

This release includes several backwards incompatible changes, most notably it requires Python 3.8 or higher.

• Rename the deploy directory to public and the attribute dir_deploy to dir_public.
• Only rebuilt the index in serve mode when a requested URL is not in the index.
• Load site settings once during initialization. Changes to site.yaml are visible only after restarting the server.
• The template to use for a file in content must be specified as the header attribute template.
• Markdown extensions are configurable in site.yaml. By default no extensions will be used.
• Pre-render content attributes on demand by setting the pre_render document attribute to a list of attribute names.
• Removed canonical template variable.
• The languages setting for multilingual sites and the auto-prefixing of collection URLs with language codes changed.