Scales the coordinates by a 'scale' factor. If not provided,
assumed to be the centroid size. It involves three steps: centering from current position,
dividing coordinates by 'scale', pusing back to the original position.
Usage
coo_scale(coo, scale)
Arguments
coo
a matrix of (x; y) coordinates or a list, or any Coo object.
scale
the scaling factor, by default, the centroid size.