Update README

* Update feature list
* Include links to guides

Author: hiddeco

README.md

@@ -7,8 +7,8 @@
 
 The helm-controller is a Kubernetes operator, allowing one to declaratively
 manage Helm chart releases. It is part of a composable [GitOps toolkit](https://toolkit.fluxcd.io)
-and depends on [source-controller](https://github.com/fluxcd/source-controller)
-to acquire the Helm charts from Helm repositories.
+and depends on [source-controller][] to acquire the Helm charts from Helm
+repositories.
 
 The desired state of a Helm release is described through a Kubernetes Custom
 Resource named `HelmRelease`. Based on the creation, mutation or removal of a
@@ -17,16 +17,35 @@ operator.
 
 ![overview](docs/diagrams/helm-controller-overview.png)
 
-Features:
-
-* watches for `HelmRelease` objects
-* fetches artifacts produced by [source-controller](https://github.com/fluxcd/source-controller)
-  from `Source` objects 
-* watches `Source` objects for revision changes
-* performs Helm actions as configured in the `HelmRelease`
-* runs `HelmReleases` in a specific order, taking into account the depends-on relationship
-
-Specifications:
+## Features
+
+* Watches for `HelmRelease` objects and generates `HelmChart` objects
+* Supports `HelmChart` artifacts produced from `HelmRepository` and
+  `GitRepository` sources
+* Fetches artifacts produced by [source-controller][] from `HelmChart`
+  objects
+* Watches `HelmChart` objects for revision changes (including semver
+  ranges for charts from `HelmRepository` sources)
+* Performs automated Helm actions, including Helm tests, rollbacks and
+  uninstalls
+* Offers extensive configuration options for automated remediation
+  (rollback, uninstall, retry) on failed Helm install, upgrade or test
+  actions.
+* Runs Helm install/upgrade in a specific order, taking into account the
+  depends-on relationship defined in a set of `HelmRelease` objects
+* Reports Helm release statuses (alerting provided by
+  [notification-controller][])
+
+## Guides
+
+* [Get started with GitOps Toolkit](https://toolkit.fluxcd.io/get-started/)
+* [Manage Helm Releases](https://toolkit.fluxcd.io/guides/helmreleases/)
+* [Setup Notifications](https://toolkit.fluxcd.io/guides/notifications/)
+
+## Specifications
 
 * [API](docs/spec/v2alpha1/README.md)
 * [Controller](docs/spec/README.md)
+
+[source-controller]: https://github.com/fluxcd/source-controller
+[notification-controller]: https://github.com/fluxcd/notification-controller