New function: cf.cell_overlaps

[davidhassell]

Fixes #824

[sadielbartholomew]

Good idea for new methods, should be useful. Implementation and new testing and docs are otherwise all good but I have questioned the inconsistent underscore in the name and I have one general suggestion (plus spotted a few typos):

• Since this new cell_overlaps, as well as cellwi and cellwo which are wi/wo queries applied to a cell, it would be nice to include the new-ish open_lower=False, open_upper=False keywords we added recently to the general wi/wo queries so they can be made open or half-open.
• For the case of cell_overlaps the open-/closed-ness could do with being clarified a bit since it's a bit less direct/clear as to the role of interval openness. You state as with the other relevant methods 'The range is closed, meaning that is inclusive of its end points.' so I guess that means if the endpoint of the cell 'overlapped' with an endpoint of the range, then in the closed/inclusive default case it would be True, e.g. for cell [5, 10] and range [10, 15] it is deemed to overlap (True)? It would be good to add either a brief sentence or a new docstring example to clarify that.

Happy to approve once you'd considered those. Thanks.

[sadielbartholomew]

General comment, but the import listing here emphasises it: all of the other queries are named without underscores, where words are merged without delimiter e.g. gt, cellsize. cellgt and cellwi etc. So I advise for consistency we do the same here (obviously the name change here would need propagating as well as this GH suggestion):

Suggested change

	cell_overlaps,
	celloverlaps,