Best Seller Query: add sublist and variations options availble from Keepa.com

[anova-git]

Python Keepa API does not have the parameters "sublist" and "variations" available from the Keepa API. They are helpful, and currently, I only receive a bestseller list similar to the one on the Amazon website, using the parameters sublist=1 (not default) and variations=0 (default).

The suggested changes are:

def best_sellers_query(
        self, category, rank_avg_range=0, **sublist=0, variations=0,** domain: Union[str, Domain] = "US", wait=True ):
        ...
       payload = {
            "key": self.accesskey,
            "domain": _domain_to_dcode(domain),
            "category": category,
            "range": rank_avg_range,
            **"sublist": sublist,
            "variations": variations**
        }
        ....

And probably a validation of the new parameters.

Thanks,