Moved source code under src folder - massive change

src/Marr.Data/EntityReference.cs

@@ -0,0 +1,28 @@
+using System.Collections.Generic;
+using System.Collections;
+
+namespace Marr.Data
+{
+    /// <summary>
+    /// Stores an entity along with all of its 1-M IList references.
+    /// </summary>
+    public class EntityReference
+    {
+        public EntityReference(object entity)
+        {
+            Entity = entity;
+            ChildLists = new Dictionary<string, IList>();
+        }
+
+        public object Entity { get; private set; }
+        public Dictionary<string, IList> ChildLists { get; private set; }
+
+        public void AddChildList(string memberName, IList list)
+        {
+            if (ChildLists.ContainsKey(memberName))
+                ChildLists[memberName] = list;
+            else
+                ChildLists.Add(memberName, list);
+        }
+    }
+}