Move samples into groups -- same groups have identical names.

def _group_same_samples(ldetails):
    """Move samples into groups -- same groups have identical names.
    """
    sample_groups = collections.defaultdict(list)
    for ldetail in ldetails:
        sample_groups[ldetail["name"]].append(ldetail)
    return sorted(sample_groups.values(), key=lambda xs: xs[0]["name"])