MP campaign additions/fixes:

- Store tab & cargo spawning
- Sub & shuttle lists and level seed box are disabled when a campaign is active.
- Campaign UI is recreated if a new campaign is started while another one is active.

Barotrauma/BarotraumaClient/Source/GUI/GUIListBox.cs

@@ -80,7 +80,11 @@ namespace Barotrauma
         public bool Enabled
         {
             get { return enabled; }
-            set { enabled = value; }
+            set
+            {
+                enabled = value;
+                scrollBar.Enabled = value;
+            }
         }
 
         public override Color Color
@@ -280,7 +284,7 @@ namespace Barotrauma
 
             UpdateChildrenRect(deltaTime);
             
-            //base.Update(deltaTime);
+            if (!enabled) return;
 
             if (scrollBarEnabled && !scrollBarHidden) scrollBar.Update(deltaTime);