重写了节点的view、viewmodel关系，实现了对画布元素的选取功能，重构了底层依赖，添加了对net .Framework4.6.1以上的Framework类库支持

Library.Framework/NodeFlow/DynamicContext.cs

@@ -0,0 +1,40 @@
+using Serein.Library.Api;
+using Serein.Library.Utils;
+using System;
+using System.Threading.Tasks;
+
+namespace Serein.Library.Framework.NodeFlow
+{
+
+
+    /// <summary>
+    /// 动态流程上下文
+    /// </summary>
+    public class DynamicContext : IDynamicContext
+    {
+        public DynamicContext(ISereinIoc sereinIoc)
+        {
+            SereinIoc = sereinIoc;
+        }
+
+        public NodeRunCts NodeRunCts { get; set; }
+        public ISereinIoc SereinIoc { get; }
+        public Task CreateTimingTask(Action action, int time = 100, int count = -1)
+        {
+            if(NodeRunCts == null)
+            {
+
+                NodeRunCts = SereinIoc.GetOrInstantiate<NodeRunCts>();
+            }
+            return Task.Factory.StartNew(async () =>
+            {
+                for (int i = 0; i < count; i++)
+                {
+                    NodeRunCts.Token.ThrowIfCancellationRequested();
+                    await Task.Delay(time);
+                    action.Invoke();
+                }
+            });
+        }
+    }
+}