Add project files.

OemanTrader.WPF/State/Navigators/INavigator.cs

@@ -0,0 +1,21 @@
+using OemanTrader.WPF.ViewModels;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Input;
+
+namespace OemanTrader.WPF.State.Navigators
+{
+    public enum ViewType
+    {
+        Home,
+        Portfolio
+    }
+    public interface INavigator
+    {
+        ViewModelBase CurrentViewModel { get; set; }
+        ICommand UpdateCurrentViewModelCommand { get; }
+    }
+}