Add a readme for the tinkerbell stack chart. (#2528)

Signed-off-by: Jacob Weinstock <[email protected]>

projects/tinkerbell/tinkerbell-chart/README.md

@@ -0,0 +1,16 @@
+# **Tinkerbell Stack Helm Chart**
+
+## Updating
+
+1. Make your changes to the chart.
+1. When copying CRDs from upstream, make sure CRDs that will/need to be moved around by `clusterctl move` have the appropriate labels.
+
+    ```yaml
+    labels:
+      clusterctl.cluster.x-k8s.io: ""
+      clusterctl.cluster.x-k8s.io/move: ""
+    ```
+
+1. Bump the version, appropriately, in the following files: `GIT_TAG`, `helm/sedfile.template`, and `chart/Chart.yaml`.
+1. Run `make verify` to verify the chart.
+1. Commit and push your changes.