New feature: Cell size correction

In the latest version of Zonation (v4) it is possible to account for varying cell size within input layers. This feature is useful for example when input data is using geodetic coordinate system. The feature has not yet been documented in the manual, but is fully functional.

To use cell size correction add following line to the settings file (.dat): cell area layer = path_to_a_raster_layer_indicating _cell_size