Implement PixelDataMatrix. (#1494)
Implement PixelDataMatrix. (#1494)

Eigen::Matrix (or Eigen::Array) with custom scalar types is
not intended for arbitrary structs:
https://eigen.tuxfamily.org/dox/TopicCustomizing_CustomScalar.html

This implements a simple class as a replacement.
cartographer-project/cartographer,wohe/cartographer,googlecartographer/cartographer,googlecartographer/cartographer,cartographer-project/cartographer,damonkohler/cartographer,larics/cartographer,googlecartographer/cartographer,googlecartographer/cartographer,larics/cartographer,damonkohler/cartographer,larics/cartographer,wohe/cartographer,wohe/cartographer,cartographer-project/cartographer,wohe/cartographer,damonkohler/cartographer,cartographer-project/cartographer,damonkohler/cartographer,larics/cartographer