Documentation of resample_image/resample_data largely missing

[cpaulik]

It would be great to have a minimal example as a test and/or in the documentation.
From the docstrings here and here it is very difficult to figure out how this is supposed to work.

[cpaulik]

A more general question might even be if we want to support this at this level for image datasets? Maybe I am missing something but probably the easiest way of producing a resampled dataset would be to subclass and overwrite the read method? In this way there is no need to extend the interface.