I'm not thrilled with the `replace` error handler losing information
if the logfile contains invalid UTF-8 for some reason; but that sure
beats a UnicodeDecodeError, and for this script I can't quite be
bothered to run the rather tricky riddle trail that Python 3 makes it
to pass arbitrary byte data through layers of ordinary text processing.
In order to keep all three packages (zulip, zulip_bots,
zulip_botserver) in the same repo, all package files must now
be nested one level deeper.
For instance, python-zulip-api/zulip_bots/zulip_bots/bots/, instead
of python-zulip-api/zulip_bots/bots/.