The github-services model for how GitHub would send requests to this
legacy integration is no longer available since earlier in 2019.
Removing this integration also allows us to finally remove
authenticated_api_view, the legacy authentication model from 2013 that
had been used for this integration (and other features long since
upgraded).
A few functions that were used by the Beanstalk webhook are moved into
that webhook's implementation directly.
This directory contains scripts that are used in building, managing,
testing, and other forms of work in a Zulip development environment.
Note that tools that are also useful in production belong in
scripts/ or should be Django management commands.