dataset_search finds both the depreciated and new dataset names

[PierreGtch]

Since #464, dataset_search will return both the depreciated and the new name of each dataset. Also, it raises a warning for every depreciated dataset because they are all initialized.

[sylvchev]

@PierreGtch could you check if it is still the case?

[PierreGtch]

@sylvchev it’s still the case rn but removing them is simple (see PR).

The issue is that I don't know if some applications need to also have the old names in the search results. Is this a breaking change?

[sylvchev]

For me this is not a breaking change as the new names are the one that should be used. Better not advertise deprecated names.

[PierreGtch]

ok then we can merge #504