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/Farseer Physics Engine 3.5/Common/Decomposition/Seidel/Point.cs

@@ -0,0 +1,61 @@
+namespace FarseerPhysics.Common.Decomposition.Seidel
+{
+    internal class Point
+    {
+        // Pointers to next and previous points in Monontone Mountain
+        public Point Next, Prev;
+        public float X, Y;
+
+        public Point(float x, float y)
+        {
+            X = x;
+            Y = y;
+            Next = null;
+            Prev = null;
+        }
+
+        public static Point operator -(Point p1, Point p2)
+        {
+            return new Point(p1.X - p2.X, p1.Y - p2.Y);
+        }
+
+        public static Point operator +(Point p1, Point p2)
+        {
+            return new Point(p1.X + p2.X, p1.Y + p2.Y);
+        }
+
+        public static Point operator -(Point p1, float f)
+        {
+            return new Point(p1.X - f, p1.Y - f);
+        }
+
+        public static Point operator +(Point p1, float f)
+        {
+            return new Point(p1.X + f, p1.Y + f);
+        }
+
+        public float Cross(Point p)
+        {
+            return X * p.Y - Y * p.X;
+        }
+
+        public float Dot(Point p)
+        {
+            return X * p.X + Y * p.Y;
+        }
+
+        public bool Neq(Point p)
+        {
+            return p.X != X || p.Y != Y;
+        }
+
+        public float Orient2D(Point pb, Point pc)
+        {
+            float acx = X - pc.X;
+            float bcx = pb.X - pc.X;
+            float acy = Y - pc.Y;
+            float bcy = pb.Y - pc.Y;
+            return acx * bcy - acy * bcx;
+        }
+    }
+}