code: public static <T> ISeq<Vec<T>> front(final Seq<? extends Vec<T>> set) {
  		return front(set, Vec::dominance);
  	}
docs: Return the elements, from the given input {@code set}, which are part of
  the pareto front. The {@link Comparable} interface defines the dominance
  measure of the elements, used for calculating the pareto front.
  <p>
  <b>Reference:</b><em>
  E. Zitzler and L. Thiele.
  Multiobjective Evolutionary Algorithms: A Comparative Case Study
  and the Strength Pareto Approach,
  IEEE Transactions on Evolutionary Computation, vol. 3, no. 4,
  pp. 257-271, 1999.</em>
  
  @param set the input set
  @param <T> the element type
  @return the elements which are part of the pareto set
  @throws NullPointerException if one of the arguments is {@code null}