[canvas2d]Make examples live in a namespace.

UnityProject/Assets/GraphFramework/Canvas2D/Editor/Examples/Animation/AnimationCanvas2D.cs

-using System;
-using UnityEditor.Experimental;
-using Object = UnityEngine.Object;
-namespace UnityEditor
+namespace UnityEditor.Experimental.Graph.Examples
 {
     internal class AnimationCanvas2D : EditorWindow
     {

UnityProject/Assets/GraphFramework/Canvas2D/Editor/Examples/Animation/AnimationDataSource.cs

-using System;
-using UnityEngine;
-using UnityEditor.Experimental;
-using UnityEditor.Experimental.Graph;
-using Object = UnityEngine.Object;
-namespace UnityEditor
+namespace UnityEditor.Experimental.Graph.Examples
 {
     internal class AnimationDataSource : ICanvasDataSource
     {

UnityProject/Assets/GraphFramework/Canvas2D/Editor/Examples/Animation/FlexBox.cs

-using System;
-using System.Collections.Generic;
-using System.Text.RegularExpressions;
-using System.IO.Pipes;
-using System.Linq;
-using System.Linq.Expressions;
-using System.Security.Cryptography;
-using System.Text;
-using System.IO;
-using System.Reflection;
-using UnityEditor.Animations;
-using UnityEditor.Experimental;
-using UnityEditorInternal;
-using UnityEngine.Experimental.Director;
-using Object = UnityEngine.Object;
-namespace UnityEditor
+namespace UnityEditor.Experimental.Graph.Examples
 {
     class ColoredBlockUI : CanvasElement
     {

UnityProject/Assets/GraphFramework/Canvas2D/Editor/Examples/Nodal/NodalCanvas2D.cs

 using UnityEngine;
-using UnityEditor.Experimental;
-namespace UnityEditor
+namespace UnityEditor.Experimental.Graph.Examples
 {
     internal class NodalCanvas2D : EditorWindow
     {

UnityProject/Assets/GraphFramework/Canvas2D/Editor/Examples/Nodal/NodalDataSource.cs

 using System.Collections.Generic;
 using UnityEngine;
-using UnityEditor.Experimental;
-using UnityEditor.Experimental.Graph;
-namespace UnityEditor
+namespace UnityEditor.Experimental.Graph.Examples
 {
     internal class NodalDataSource : ICanvasDataSource
     {

UnityProject/Assets/GraphFramework/Canvas2D/Editor/Examples/Nodal/NodalWidgets.cs

 using System;
 using UnityEngine;
-using UnityEditor.Experimental;
-using UnityEditor.Experimental.Graph;
-namespace UnityEditor
+namespace UnityEditor.Experimental.Graph.Examples
 {
     class PortSource<T>
     {

UnityProject/Assets/GraphFramework/Canvas2D/Editor/Examples/Simple/ExampleWidgets.cs

 using UnityEngine;
-using UnityEditor.Experimental;
-namespace UnityEditor
+namespace UnityEditor.Experimental.Graph.Examples
 {
     class SimpleBox : CanvasElement
     {

UnityProject/Assets/GraphFramework/Canvas2D/Editor/Examples/Simple/SimpleCanvas2D.cs

 #pragma warning disable 0414
 #pragma warning disable 0219
 
-namespace UnityEditor
+namespace UnityEditor.Experimental.Graph.Examples
 {
     internal class SimpleCanvas2D : EditorWindow
     {

UnityProject/Assets/GraphFramework/Canvas2D/Editor/Examples/Simple/SimpleDataSource.cs

 using System.Collections.Generic;
 using UnityEngine;
-using UnityEditor.Experimental;
-namespace UnityEditor
+namespace UnityEditor.Experimental.Graph.Examples
 {
     internal class SimpleDataSource : ICanvasDataSource
     {