This is a preparatory commit for using isort for sorting all of our
imports, merging changes to files where we can easily review the
changes as something we're happy with.
These are also files with relatively little active development, which
means we don't expect much merge conflict risk from these changes.
This new setting controls whether or not users are allowed to see the
edit history in a Zulip organization. It controls access through 2
key mechanisms:
* For long-ago edited messages, get_messages removes the edit history
content from messages it sends to clients.
* For newly edited messages, clients are responsible for checking the
setting and not saving the edit history data. Since the webapp was
the only client displaying it before this change, this just required
some changes in message_events.js.
Significantly modified by tabbott to fix some logic bugs and add a
test.
Tim Abbott
rht
Durga Akhil Mundroy