Updated to MonoGame 3.6 + Directory refactor

- Barotrauma's projects are in the Barotrauma directory
- All libraries are in the Libraries directory
- MonoGame is now managed by NuGet, rather than referenced from the installed files (TODO: consider using PCL for easier cross-platform development?)
- NuGet libraries are not included in the repo, as getting the latest versions automatically should be preferred
- Removed Content/effects.mgfx as it didn't seem to be used anywhere
- Removed some references to Subsurface directory
- Renamed Launcher2 to Launcher

Barotrauma/BarotraumaServer/Source/Networking/GameClient.cs

@@ -0,0 +1,19 @@
+using System;
+using Lidgren.Network;
+using Microsoft.Xna.Framework;
+using System.Collections.Generic;
+using System.IO;
+using System.Text;
+using System.ComponentModel;
+using System.Linq;
+
+namespace Barotrauma.Networking
+{
+    class GameClient : NetworkMember
+    {
+        public GameClient(string newName)
+        {
+            throw new Exception("Tried to create GameClient in dedicated server build");
+        }
+    }
+}