Add details for terragrunt native state management (#1015)

Will be in private beta this week (mid-Jan), GA soon (but not yet).

Author: KiraLempereur-Spacelift

docs/assets/screenshots/terragrunt-native-state-management.png

@@ -11,6 +11,9 @@ Whether a Terraform stack is using Terragrunt or not is controlled by the presen
 
 If present, all workloads will use `terragrunt` instead of `terraform` as the main command. Since the Terragrunt API is a superset of Terraform's, this is completely transparent to the end user.
 
+!!! info
+    Spacelift is working to enable [native state management](../terragrunt/limitations.md#state-management) for Terragrunt. The `terragrunt` label will be deprecated.
+
 Terragrunt is installed on our [standard runner image](../../integrations/docker.md#standard-runner-image). If you're not using our runner image, you can [install Terragrunt separately](https://terragrunt.gruntwork.io/docs/getting-started/install/#install-terragrunt){: rel="nofollow"}.
 
 During the _Initialization_ phase we're showing you the exact binary that will process your job, along with its location:

docs/vendors/terraform/terragrunt.md

@@ -4,7 +4,7 @@ description: Managing Terragrunt Stacks through Spacelift.
 # Terragrunt
 
 !!! warning
-    Terragrunt support is currently in **beta** and has some important limitations to take into consideration. Please see our documentation [here](limitations.md) for more information.
+    Terragrunt support is currently in **beta** and has some important [limitations](./limitations.md) to take into consideration.
 
 ## Why use Terragrunt?
 

docs/vendors/terragrunt/README.md

@@ -5,7 +5,7 @@ description: Creating your first Terragrunt Stack with Spacelift, step by step.
 # Getting Started
 
 !!! warning
-    Terragrunt support is currently in **beta** and has some important limitations to take into consideration. Please see our documentation [here](limitations.md) for more information.
+    Terragrunt support is currently in **beta** and has some important [limitations](./limitations.md) to take into consideration.
 
 This documentation will be using an example repository Spacelift provides [here](https://github.com/spacelift-io-examples/terragrunt-examples){: rel="nofollow"}. This repository contains two different examples, but in this guide we will use the single-stack example.
 
@@ -27,10 +27,19 @@ On the **Connect to source code** screen, Select **Raw Git** as your Provider, a
 
 Pressing continue on this page will take you through to the vendor configuration page.
 
+!!! info
+    Spacelift is working to enable native state management for Terragrunt, which will be available for private beta in mid-January. Contact your customer representative or Spacelift support for more information.
+
 This page has quite a few options but the ones that we will be using for this example are as follows:
 
 ![Stack Creation - Choose vendor](../../assets/screenshots/terragrunt/getting-started/backend.png)
 
+### Native state management option (beta)
+
+If you are part of the Terragrunt native state management beta, you will see a _Manage state_ slider. Enable it to allow Spacelift to manage the Terragrunt state.
+
+![Terragrunt native state management option](<../../assets/screenshots/terragrunt-native-state-management.png>)
+
 Press **Create & continue** to finish the backend configuration and move through to defining stack behavior. For this example nothing else needs to be configured, so you can click on **Skip to summary** and then click on **Confirm** to finish creating your stack.
 
 ## Deploying the stack

docs/vendors/terragrunt/getting-started.md

@@ -6,6 +6,9 @@ description: Details about all limitations when using Terragrunt stacks in space
 
 ## State management
 
+!!! info
+    Spacelift is working to enable native state management for Terragrunt, which will be available for private beta in mid-January. Contact your customer representative or Spacelift support for more information.
+
 Terragrunt is a great tool for organizing your state management configuration and allows you to easily define how you manage your state across multiple projects. However, It is not currently possible when using Terragrunt's run-all functionality to relate state files to projects in a consistent manner. For this reason Spacelift does not support storing state for Terragrunt based stacks, and you will need to maintain your own remote state backend configuration.
 
 ## Terragrunt mocked outputs