message: Got rid of ReadOnly validation
diff: @@ -435,11 +435,6 @@ namespace AutoRest.Go
  }
  }
  - x.AddRange(from prop in ((CompositeType)p.ModelType).Properties
  - where prop.IsReadOnly
  - select GetConstraint(string.Format("{0}.{1}", name, prop.WasFlattened() ? prop.ModelType.Name : prop.Name),
  - ReadOnlyConstraint, "true"));
  -
  List<string> y = new List<string>();
  if (x.Count > 0)
  {
  