Add Coleslaw – blog and site generator written in Common Lisp (#163)

As an example how it looks like you can see here on my site:
https://40ants.com/

It is easy to write plugins for the Coleslaw, if you have experience in
Common Lisp.

README.md

@@ -33,6 +33,7 @@ A static web site generator is an application that takes plain text files and co
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