message: Added note on a potential Landmark2f type
diff: #include <vector>
  #include <algorithm>
  +//#include <array>
  #include "Eigen/Core"
  namespace eos {
  @@ -47,6 +48,11 @@ struct Landmark
  */
  template<class LandmarkType> using LandmarkCollection = std::vector<Landmark<LandmarkType>>;
  +/**
  + * @brief Shorthand for a 2D floating point landmark type.
  + */
  +//using Landmark2f = Landmark<std::array<float, 2>>;
  +
  /**
  * @brief Alias for the 2D landmark point type.
  */
  