Add CI/CD

.gitlab-ci.yml

+# Using the node alpine image to build the React app
+image: node:latest
+
+# Announce the URL as per CRA docs
+# https://github.com/facebook/create-react-app/blob/master/packages/react-scripts/template/README.md#advanced-configuration
+variables:
+  PUBLIC_URL: /life-cycle
+# Cache node modules - speeds up future builds
+cache:
+  paths:
+  - node_modules
+
+# Name the stages involved in the pipeline
+stages:
+- deploy
+
+# Job name for gitlab to recognise this results in assets for Gitlab Pages
+# https://docs.gitlab.com/ee/user/project/pages/introduction.html#gitlab-pages-requirements
+pages:
+  stage: deploy
+  script:
+    - npm install # Install all dependencies
+    - CI=false npm run build --prod # Build for prod
+    - cp public/index.html public/404.html # Not necessary, but helps with https://medium.com/@pshrmn/demystifying-single-page-applications-3068d0555d46
+    - mv public _public # CRA and gitlab pages both use the public folder. Only do this in a build pipeline.
+    - mv build public # Move build files to public dir for Gitlab Pages
+  artifacts:
+    paths:
+    - public # The built files for Gitlab Pages to serve
+  only:
+    - master # Only run on master branch
+