default R or() {
    return Matchers.extract(this).or().create();
  }
Builds a disjunction with boolean {@code OR}.

<p>By default, boolean expressions are combined using
<a href="https://en.wikipedia.org/wiki/Disjunctive_normal_form">disjunctive normal form</a>.
@return new root criteria with updated expression
criteria/common/src/org/immutables/criteria/matcher/Disjunction.java