code: public SimulationBuilder phase(String phase) {
        phases.remove(phase);
        phases.add(phase);
        return this;
     }
docs: Adds a new phase to the phase list. If this phase is already in the phase
  list (for example because it is the default ("tick") phase
  {@link Simulation#TICK_PHASE}), it is moved to the end of the list.
  
  @param phase
  the name of the phase to add
  @return this object