code: private boolean addDependant(BuildConfiguration dependant) {
          boolean result = dependants.add(dependant);
          if (!dependant.getDependencies().contains(this)) {
              dependant.addDependency(this);
          }
          return result;
      }
docs: This method is private because a dependant should never be added externally. Instead the dependency relation should be
  set up using the addDependency method
  
  @param dependant
  @return