Ingest Phorge (Phabricator fork)

Summary:

Phorge is a fork of Phabricator and is probably compatible with the existing SWH lister for Phabricator.

The front page of Phorge has the text Welcome to Phorge but unfortunately all sites I could find in search engines are either NSFW spam sites or unrelated to Phorge but related to the word Forge.

These sites are currently running Phorge:

https://we.phorge.it/
https://git.kolab.org/

See also #5056 about supporting Phabricator in Add forge now.

Plan:

• Implement lister
• Implement loader
• docker: Run lister
• docker: Run loader
• Document lister
• Document loader
• Deploy on staging
• Call for public review
• Deploy on production