NGINX setup on Centos 8

nginx-setup-centos8.md

ToDo: Make clear & concise instructions based on these resources:

1. https://linuxize.com/post/how-to-set-up-nginx-server-blocks-on-centos-8
2. https://stackoverflow.com/questions/22586166/why-does-nginx-return-a-403-even-though-all-permissions-are-set-properly
3. https://linuxize.com/post/secure-nginx-with-let-s-encrypt-on-centos-8/