tidy the codes

src/Shared/HandyControl_Shared/Data/Enum/TipPlacement.cs

@@ -3,7 +3,64 @@ namespace HandyControl.Data
 {
     public enum TipPlacement
     {
+        /// <summary>
+        /// 左上
+        /// </summary>
+        LeftTop,
+        
+        /// <summary>
+        /// 左
+        /// </summary>
+        Left,
+        
+        /// <summary>
+        /// 左下
+        /// </summary>
+        LeftBottom,
+
+        /// <summary>
+        /// 上左
+        /// </summary>
         TopLeft,
+
+        /// <summary>
+        /// 上
+        /// </summary>
+        Top,
+
+        /// <summary>
+        /// 上右
+        /// </summary>
+        TopRight,
+
+        /// <summary>
+        /// 右上
+        /// </summary>
+        RightTop,
+        
+        /// <summary>
+        /// 右
+        /// </summary>
+        Right,
+        
+        /// <summary>
+        /// 右下
+        /// </summary>
+        RightBottom,
+               
+        /// <summary>
+        /// 下左
+        /// </summary>
+        BottomLeft,
+        
+        /// <summary>
+        /// 下
+        /// </summary>
+        Bottom,
+        
+        /// <summary>
+        /// 下右
+        /// </summary>
         BottomRight,
     }
 }