renaming the primary grid parameter from `resolution` to `level`

[keewis]

From #62:

We've decided to go with level instead of resolution or refinement_level / reflevel etc. in the meeting, as the context is enough to disambiguate between other kinds of levels. In particular, "processing level" to me is a property of the data / dataset, not the grid (not sure what you're referring to with "maturity level", but if it has to do with the data maturity I would also call that a property of the data or dataset, not the grid).

This issue is to track that change.

[strobpr]

Thanks, level is definitely better than resolution! A move in the right direction and when used in grid hierarchy context such as DGGS APIs, the term is not really ambiguous. I added a comment on the general wording to #65.

There are plenty of other 'levels' in EO and related geospatial sciences, I was referring to the levels of the WGISS Data Management and Stewardship Maturity Matrix just pointing at the fact that if the context is not crystal clear, speaking of 'data levels' might be interpretable.