Add project files.

Esiur/Resource/ResourceFunction.cs

@@ -0,0 +1,28 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Esiur.Resource
+{
+    [AttributeUsage(AttributeTargets.Method)]
+    public class ResourceFunction : System.Attribute
+    {
+        private string expansion = null;
+        
+        public string Expansion
+        {
+            get
+            {
+                return expansion;
+            }
+        }
+
+
+        public ResourceFunction(string expansion = null)
+        {
+            this.expansion = expansion;
+        }
+    }
+}