material edit windows were added

StructureHelper/Infrastructure/Enums/MaterialType.cs

@@ -0,0 +1,15 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace StructureHelper.Infrastructure.Enums
+{
+    internal enum MaterialType
+    {
+        Concrete,
+        Reinforcement,
+        Elastic
+    }
+}