Updating readme

Signed-off-by: Martyn Ranyard <m@rtyn.berlin>

README.md

@@ -3,3 +3,62 @@
 A tool to take a deployed set of kubernetes resources and turn them into a helm release.
 
 Only works with helm3 > 3.2.0
+
+Only compiles with Go < 1.15
+
+And it's a pain to cross-compile, and my ci is currently broken
+
+You can add jq commands to tweak the generation.
+
+You run it from the chart folder (the one with `Chart.yaml`) in it
+
+It's fairly opinionated but that can be turned off.
+
+There's some kinda hacky stuff in the code related to json->yaml->helm stuff.
+
+so... erm here's a docker command that worked for me :
+
+```
+docker run -v $(pwd):/context -v $HOME/.kube:/root/.kube --rm -it -w /context/ imartyn/helm-import /helm-import -namespace some-namespace -deployment some-deployment
+```
+
+and here's the help screen :
+```
+Usage of helm-import:
+  -configmap value
+        configmap to import into the helm chart (can be specified multiple times)
+  -configmapJqCommands value
+        extra jq commands to apply to configmaps
+  -deployment value
+        deployment to import into the helm chart (can be specified multiple times)
+  -deploymentJqCommands value
+        extra jq commands to apply to deployments
+  -globalJqCommands value
+        extra jq commands to apply to all k8s objects
+  -ingress value
+        ingress to import into the helm chart (can be specified multiple times)
+  -ingressJqCommands value
+        extra jq commands to apply to ingresses
+  -kubeconfig string
+        (optional) absolute path to the kubeconfig file (default "/home/martyn/.kube/config")
+  -lessopinions
+        just import the objects into files, don't get opinionated
+  -namespace string
+        namespace to work in (default "default")
+  -nobuiltinmods
+        don't do the built-in modifications, only ones passed in by user
+  -secret value
+        secret to import into the helm chart (can be specified multiple times)
+  -secretJqCommands value
+        extra jq commands to apply to secrets
+  -service value
+        service to import into the helm chart (can be specified multiple times)
+  -serviceJqCommands value
+        extra jq commands to apply to services
+
+```
+
+TODO:
+- [ ] label the resources
+- [ ] make ci work again
+- [ ] cross-compile, now I know it was a go-1.15 issue first time