`porosity_profile` could use a bit more control

[jgostick]

There is a new function called saturation_profile which has several options, like mode= 'sliding' or 'tiled' and span (which controls the window size). I think these types of options should be added to porosity_profile too.

[jgostick]

In fact, it could probably just pass the args to satn_profile and use that function behind the scenes.