VariantDataset.rename_samples now takes a dict

VariantDataset.rename_samples now takes a dict instead of the path to a mapping file.

The old behavior can be achieved by importing the mapping as a KeyTable and converting it to a dict, for example:

d = {r._0: r._1 for r in (hc.import_keytable('/path/to/sample.map',
                                             config=TextTableConfig(noheader=True))
                          .collect())}
renamed_vds = vds.rename_samples(d)

It is also possible to programatically rename samples, for example, to convert spaces to underscores:

m = {id: id.replace(' ', '_') for id in vds.sample_ids if ' ' in id}
renamed_vds = vds.rename_samples(m)