The functions add_dependencies() and set_global() are convenience
methods that allow you to modify the global namespace while
the current file is running but then have it be cleaned up
by index.js when you're done.
(imported from commit f75b8a10c19f773a8d2d3a8fa4bc39b1679566fe)
There are also one or two places we don't need to use it for security
purposes, but we do so for consistencey.
(imported from commit aa111f5a22a0e8597ec3cf8504adae66d5fb6768)
This needs to be deployed to both staging and prod at the same
off-peak time (and the schema migration run).
At the time it is deployed, we need to make a few changes directly in
the database:
(1) UPDATE django_content_type set app_label='zerver' where app_label='zephyr';
(2) UPDATE south_migrationhistory set app_name='zerver' where app_name='zephyr';
(imported from commit eb3fd719571740189514ef0b884738cb30df1320)