@author Daniel Lehmberg
Processor counts number of pedestrians in a measurement area of any shape.
To avoid unneccessary complicated structures this class does *not* extend from @AreaDensityProcessor (which requires
an intern class or a separate class implementing the density algorithm). However, AreaDensityProcessor is a better
description of what the processor does.
See e.g. AreaDensityVoronoiProcessor / AreaDensityVoronoiAlgorithm