Fixes U4-2097 Package import causes template tree to break

src/Umbraco.Core/Models/Template.cs

@@ -28,12 +28,8 @@ namespace Umbraco.Core.Models
         {
             base.Path = path;
             ParentId = -1;
-            Key = name.EncodeAsGuid();
             _name = name.Replace("/", ".").Replace("\\", "");
             _alias = alias.ToSafeAlias();
-
-            CreateDate = DateTime.Now;
-            UpdateDate = DateTime.Now;
         }
 
         [DataMember]
@@ -116,5 +112,17 @@ namespace Umbraco.Core.Models
 
             return validFile && validExtension;
         }
+
+        /// <summary>
+        /// Method to call when Entity is being saved
+        /// </summary>
+        /// <remarks>Created date is set and a Unique key is assigned</remarks>
+        internal override void AddingEntity()
+        {
+            base.AddingEntity();
+
+            if (Key == Guid.Empty)
+                Key = Guid.NewGuid();
+        }
     }
 }