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

Libraries/Lidgren.Network/NetSendResult.cs

@@ -0,0 +1,30 @@
+using System;
+
+namespace Lidgren.Network
+{
+	/// <summary>
+	/// Result of a SendMessage call
+	/// </summary>
+	public enum NetSendResult
+	{
+		/// <summary>
+		/// Message failed to enqueue because there is no connection
+		/// </summary>
+		FailedNotConnected = 0,
+
+		/// <summary>
+		/// Message was immediately sent
+		/// </summary>
+		Sent = 1,
+
+		/// <summary>
+		/// Message was queued for delivery
+		/// </summary>
+		Queued = 2,
+
+		/// <summary>
+		/// Message was dropped immediately since too many message were queued
+		/// </summary>
+		Dropped = 3
+	}
+}