Modified some namespaces (#3533)

* Added the MLAgents.Demonstrations namespace

* Added the MLAgents.Editor namespace

* Overrided the .demo.meta files due to the change in namespace

* More namespace changes

* Added the sidechannels namespace

* Modified changelog and migrating docs

Author: vincentpierre

Project/Assets/ML-Agents/Examples/3DBall/Scripts/Ball3DAgent.cs

@@ -1,6 +1,7 @@
 using UnityEngine;
 using MLAgents;
 using MLAgents.Sensors;
+using MLAgents.SideChannels;
 
 public class Ball3DAgent : Agent
 {

Project/Assets/ML-Agents/Examples/3DBall/Scripts/Ball3DHardAgent.cs

@@ -1,6 +1,7 @@
 using UnityEngine;
 using MLAgents;
 using MLAgents.Sensors;
+using MLAgents.SideChannels;
 
 public class Ball3DHardAgent : Agent
 {

Project/Assets/ML-Agents/Examples/Bouncer/Scripts/BouncerAgent.cs

@@ -1,6 +1,7 @@
 using UnityEngine;
 using MLAgents;
 using MLAgents.Sensors;
+using MLAgents.SideChannels;
 
 public class BouncerAgent : Agent
 {

Project/Assets/ML-Agents/Examples/GridWorld/Scripts/GridArea.cs

@@ -2,6 +2,7 @@
 using UnityEngine;
 using System.Linq;
 using MLAgents;
+using MLAgents.SideChannels;
 
 
 public class GridArea : MonoBehaviour

Project/Assets/ML-Agents/Examples/SharedAssets/Scripts/ModelOverrider.cs

@@ -4,6 +4,7 @@
 using Barracuda;
 using System.IO;
 using MLAgents;
+using MLAgents.Policies;
 
 namespace MLAgentsExamples
 {

Project/Assets/ML-Agents/Examples/Soccer/Scripts/AgentSoccer.cs

@@ -1,6 +1,7 @@
 using System;
 using UnityEngine;
 using MLAgents;
+using MLAgents.Policies;
 
 public class AgentSoccer : Agent
 {

Project/Assets/ML-Agents/Examples/Tennis/Scripts/TennisAgent.cs

@@ -2,6 +2,7 @@
 using UnityEngine.UI;
 using MLAgents;
 using MLAgents.Sensors;
+using MLAgents.SideChannels;
 
 public class TennisAgent : Agent
 {

Project/Assets/ML-Agents/Examples/Walker/Scripts/WalkerAgent.cs

@@ -2,6 +2,7 @@
 using MLAgents;
 using MLAgentsExamples;
 using MLAgents.Sensors;
+using MLAgents.SideChannels;
 
 public class WalkerAgent : Agent
 {

com.unity.ml-agents/CHANGELOG.md

@@ -1,6 +1,7 @@
 using MLAgents.Sensors;
 using UnityEditor;
 using Barracuda;
+using MLAgents.Policies;
 
 namespace MLAgents.Editor
 {
@@ -75,7 +76,7 @@ void DisplayFailedModelChecks()
             }
             if (brainParameters != null)
             {
-                var failedChecks = InferenceBrain.BarracudaModelParamLoader.CheckModel(
+                var failedChecks = Inference.BarracudaModelParamLoader.CheckModel(
                     barracudaModel, brainParameters, sensorComponents);
                 foreach (var check in failedChecks)
                 {