Added option to toggle vsync

For the ultimate PC master race experience.

Also calling water scroll on every frame with deltatime instead of being called at fixed intervals, making it look smoother as framerate increases.

Subsurface/Source/GUI/LoadingScreen.cs

@@ -101,6 +101,7 @@ namespace Barotrauma
 
             if (Hull.renderer != null)
             {
+                Hull.renderer.ScrollWater(deltaTime);
                 Hull.renderer.RenderBack(spriteBatch, renderTarget, 0.0f);
             }
             
@@ -134,13 +135,13 @@ namespace Barotrauma
 
         }
 
-        public void Update()
+        /*public void Update()
         {
             if (Hull.renderer != null)
             {
                 Hull.renderer.ScrollWater();
             }
-        }
+        }*/
 
         bool drawn;
         public IEnumerable<object> DoLoading(IEnumerable<object> loader)