Convert to PEP-517. Undeprecate consumers. The Scrapy framework has been devided amongst several maintainers, including myself, which isn't an ideal situation. textproc/py-parsel, being part and parcel (pun intended) to the whole operation hasn't been updated in ~6 years. This port is well past its EXPIRATION_DATE, with no maintainer input, so I figure all is fair at this point to save Scrapy.