10.1.0: Add new Ubuntu 22.04, replace nginx installation steps, add njs module

Major Changes

• Add new base from Ubuntu 20.04 (docker-base:5.0.1-ubuntu-20.04) to Ubuntu 22.04 (docker-base:5.1.0-ubuntu-22.04). Will eventually make this the default
• Removed previous nginx installation from ppa:ondrej/nginx and software-properties-common
• Removed curl, gnupg2 if installed
• Added new install nginx script scripts/install_nginx.sh, from standard nginx install: http://nginx.org/en/linux_packages.html#Ubuntu
• Added new install njs module script scripts/install_njs.sh to install nginx-module-njs module. See ETHOS-36876 @kmashint - https://nginx.org/en/docs/njs/
• Added new cleanup script scripts/cleanup.sh to purge unnecessary packages in final image
• Added SERVER_ENABLE_NGX_HTTP_JS. If set to true, it will enable i.e. load_module the nginx njs module
• Updated Ubuntu Dockerfile to use multi-stage builds

Bug Fixes

• Fix duplicate extension warning due to grep -x not matching any previous entries. Sample error

  nginx: [warn] duplicate extension "woff", content type: "font/woff", previous content type: "font/woff" in /etc/nginx/mime.types:100
  nginx: [warn] duplicate extension "woff2", content type: "font/woff2", previous content type: "font/woff2" in /etc/nginx/mime.types:101

Doc Changes

• Add deprecated messages to Alpine, CentOS
• Move most of the docs to docs/
• Add additional output in docs/ when testing HTTPS usage locally
• Add quickstart
• Add troubleshooting

CI Changes

• Updated ci and publish jobs to build the new image with -ubuntu-22.04 tag

Other Changes

• Add Makefile for common local dev operations

See #85