public class GradleUserManualPlugin implements Plugin<Project> {

    public static final String DOCS_GRADLE_ORG = "https://docs.gradle.org/";

    @Override
    public void apply(Project project) {
        ProjectLayout layout = project.getLayout();
        TaskContainer tasks = project.getTasks();

        GradleDocumentationExtension extension = project.getExtensions().getByType(GradleDocumentationExtension.class);