simple web for let's encrpty
install racket libpng ...
git clone https://github.com/Neilpang/acme.sh git clone https://github.com/connor2059/simpleweb
chmod +x simpleweb/start.sh
simpleweb/start.sh & acme.sh/acme.sh --issue -d www.example.com -w ./simpleweb/htdocs/