Updated README

README.md

@@ -1,2 +1,16 @@
-# butane
-Butane Configurations (e.g. for Flatcar Linux)
+# Butane Configurations
+
+[![Build](https://github.com/jinglemansweep/butane/actions/workflows/build.yml/badge.svg)](https://github.com/jinglemansweep/butane/actions/workflows/build.yml)
+
+## Usage
+
+    wget -O ./ignition.json https://jinglemansweep.github.io/butane/swarm_worker.json
+    flatcar-install -d /dev/vda -i ./ignition.json
+
+## Development
+
+Update Terraform and included section parts:
+
+* New configurations need to be added to both [`main.tf`](./terraform/main.tf), [`outputs.tf`](./terraform/outputs.tf) and the GitHub Actions workflow (e.g. [`build.yml`](./.github/workflows/build.yml))
+* Pushes to `main` will trigger a rebuild of configured Butane configurations
+* Resulting Ignition JSON files are published to GitHub Pages branch (`gh-pages`)