code: public ItemRequest<Project> addCustomFieldSetting(String project) {
      
          String path = String.format("/projects/%s/addCustomFieldSetting", project);
          return new ItemRequest<Project>(this, Project.class, path, "POST");
      }
docs: Create a new custom field setting on the project.
  
  @param  project The project to associate the custom field with
  @return Request object