message: Remove now unused size methods from Population
diff: @@ -14,9 +14,6 @@ public:
  void clear();
  - int size() const { return mPopulation.size(); }
  - int size(PopulationTable::Role role) const { return mPopulation.size(role); }
  -
  const PopulationTable& getPopulations() const;
  void addPopulation(const PopulationTable& population);
  