clarify input system docs

Assets/Scenes/InputSystem/InputSystem.unity

   - component: {fileID: 762671672}
   - component: {fileID: 762671671}
   - component: {fileID: 762671670}
-  - component: {fileID: 762671669}
   - component: {fileID: 762671676}
   m_Layer: 0
   m_Name: AR Session Origin
   m_StaticEditorFlags: 0
   m_IsActive: 1
---- !u!114 &762671669
-MonoBehaviour:
-  m_ObjectHideFlags: 0
-  m_CorrespondingSourceObject: {fileID: 0}
-  m_PrefabInstance: {fileID: 0}
-  m_PrefabAsset: {fileID: 0}
-  m_GameObject: {fileID: 762671668}
-  m_Enabled: 0
-  m_EditorHideFlags: 0
-  m_Script: {fileID: 11500000, guid: 7d5359d5f13250e4485741ed685a32be, type: 3}
-  m_Name: 
-  m_EditorClassIdentifier: 
-  m_PlacedPrefab: {fileID: 1934569588295450, guid: b34b6c8f1206a6844b983e23b9da0441,
-    type: 3}
 --- !u!114 &762671670
 MonoBehaviour:
   m_ObjectHideFlags: 0

README.md

 This sample scene demonstrates the functionality of the `XR Interaction Toolkit` package. In the scene, you are able to place a cube on a plane which you can translate, rotate and scale with gestures. See the [`XR Interaction Toolkit Documentation`](https://docs.unity3d.com/Packages/com.unity.xr.interaction.toolkit@0.9/manual/index.html) for more details.
 
 ## Input System
-This sample demonstrates a version of the SimpleAR scene using Unity's new Input System. See the [`Input System Documentation`](https://docs.unity3d.com/Packages/com.unity.inputsystem@1.0/manual/index.html) for more details.
+This sample demonstrates a version of the SimpleAR scene using Unity's new Input System. See `ARController.inpucations` for an example of an action map. For a demonstration on how these action map bindings are used, see the `InputSystem_PlaceOnPlane.cs` script. For more details, see the [`Input System Documentation`](https://docs.unity3d.com/Packages/com.unity.inputsystem@1.0/manual/index.html).
 
 # Community and Feedback