Remove link to all categories. It's useless with just three of them.
Found and fixed a template bug wich prevent assets plugin to work on publish deploy. This had forced to use Pelican in debug mode to deploy correctly, but with no css minification. It was related to cssprefixer, which is disabled now as I don't need to auto prefix css to vendor specific features.
Update python package requirements to remove cssprefixer.
Add a new style for strikethrough text.