* Refactor `pelican.server` logging
* Fix bug in which all static files were processed as "draft"
* Bug fixes for Invoke/Makefile automation, Importer, and other miscellanea
If upgrading from 3.7.x or earlier, please note that slug-related settings in 4.0+ use `{slug}` and/or `{lang}` rather than `%s`. If `%s`-style settings are encountered, Pelican will emit a warning and fall back to the default setting. Some user-submitted themes might try to format setting values but fail upon site build with a `TypeError`. In such cases, the theme needs to be updated. For example, instead of `TAG_FEED_ATOM|format(tag.slug)`, use `TAG_FEED_ATOM.format(slug=tag.slug)`