Updated documentation.

  cso.s5p.chocho.convert.output.var.latitude.from                    :   PRODUCT/latitude

  cso.s5p.chocho.convert.output.var.latitude.attrs                   :   { 'bounds' : None }

The pixel boundaries are necessary to know the exact footprint of a pixel,

which is for example used when averaging over a grid or simulation from a model.

These are available in the input files, but without a ``units`` attribute as these

are implied by the pixel center coordinate; the conversion therefore requires that

units are defined explicitly.

For the ``longitude_bounds`` a special processing is needed for pixels crossing the dateline,

as the original data simply uses longitudes modulo 360 degrees::

  ! corner longitudes; no units in file:

  cso.s5p.chocho.convert.output.var.longitude_bounds.dims            :   pixel corner

  cso.s5p.chocho.convert.output.var.longitude_bounds.from            :   PRODUCT/SUPPORT_DATA/GEOLOCATIONS/longitude_bounds

  cso.s5p.chocho.convert.output.var.longitude_bounds.units           :   degrees_east

  ! ensure that near dateline the corners form a convex region around center

  ! (with some points outside [-180,+180] if necessary)

  cso.s5p.chocho.convert.output.var.longitude_bounds.special         :   longitude_bounds

  ! corner latitudes, no units in file:

  cso.s5p.chocho.convert.output.var.latitude_bounds.dims             :   pixel corner

  cso.s5p.chocho.convert.output.var.latitude_bounds.from             :   PRODUCT/SUPPORT_DATA/GEOLOCATIONS/latitude_bounds

  cso.s5p.chocho.convert.output.var.latitude_bounds.units            :   degrees_north

Also the locations of the pixels in the original track are copied,

since these are useful when creating plots. These cannot be copied directly but require special processing::