Add readabilipy

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readabilipy is a python fork of mozilla readability. The latter does not run well in a cf worker because it relies on a full DOM of the html. It does support jsdom as a polyfill for node, but this also does not work great on cf workers, see jsdom/jsdom#2427 and https://community.cloudflare.com/t/jsdom-in-cloudflare-worker/65769

I was hoping to deploy a standalone python worker with ReadabiliPy as a work around