CubeList.homogenise()

[bblay]

As suggested here, prune incompatible cube attributes so they can be merged. This is for users who currently nuke all attributes in order to merge. The method should report on what it's pruning. It is less obvious whether we should offer coord pruning too, so probably best leave that for now.

Suggested interface: cubes.homogenise(keep_attrs=["elderberries"])

[pelson]

iris.experimental.equalise_cubes.equalise_attributes implements.