(052ab6307) Use MonoKickstart on Linux so installing Mono is not required, fixed division by zero if the width of the server console window is 0

Barotrauma/BarotraumaShared/Source/Items/RelatedItem.cs

@@ -16,8 +16,6 @@ namespace Barotrauma
             Container
         }
 
-        public bool IsOptional { get; set; }
-
         private string[] identifiers;
 
         private string[] excludedIdentifiers;
@@ -140,8 +138,7 @@ namespace Barotrauma
         {
             element.Add(
                 new XAttribute("identifiers", JoinedIdentifiers),
-                new XAttribute("type", type.ToString()),
-                new XAttribute("optional", IsOptional));
+                new XAttribute("type", type.ToString()));
 
             if (excludedIdentifiers.Length > 0)
             {