Add support for running the site in Docker

Author: bergjohan

Dockerfile

@@ -0,0 +1,6 @@
+FROM ruby:3.0
+WORKDIR /code
+EXPOSE 4000
+COPY . .
+RUN bundle install
+CMD bundle exec jekyll serve -H 0.0.0.0

docker-compose.yml

@@ -0,0 +1,8 @@
+version: "3"
+services:
+  web:
+    build: .
+    ports:
+      - "4000:4000"
+    volumes:
+      - .:/code