numbers in scarpet better handle long type values.

If possible, numbers that can be represented as longs (seeds, etc) will be handled as longs but they will loose their longinness with a single arithmetic operation.

src/main/java/carpet/script/value/MapValue.java

@@ -202,7 +202,7 @@ public class MapValue extends AbstractListValue implements ContainerValueInterfa
     }
 
     @Override
-    public double readNumber()
+    public double readDoubleNumber()
     {
         return (double)map.size();
     }