Add a lister of all available packages in the npm registry

This diff adds a new lister in order to discover all packages available in the npm registry (https://replicate.npmjs.com/) and create loading tasks to ingest them into the archive.

At the time of writing, 839234 packages are registered in it. Next step, write a npm loader.

Related T1378 Closes #1380 (closed)

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Migrated from D706 (view on Phabricator)