Change datetime objects to timezone-aware ones

[lucassz]

Change naive datetime objects to timezone-aware ones. This has the advantage of fixing 200+ warnings when running the tests, and everything seems to work with this change.

[hdoupe]

@lucassz This is extremely helpful. Thanks for knocking this out. Just so I understand, timezone.now() is the correct way to get the date when the time zone support is enabled and make_aware is a helper function for compatibility?

[lucassz]

@hdoupe Right, yes. We just need to use make_aware in order to adapt the hardcoded times that are used as defaults (not sure whether those are absolutely needed either).

[hdoupe]

Ok, so right now, TZ is set to UTC. It seems like the old times were set to some other timezone and time_aware converts them to UTC.

I'm reading the django timezone docs now. I'm having trouble figuring out which timezone we were using before when we had USE_TZ set to True, TIME_ZONE set to UTC, but were not using timezone aware datetimes. Do you have any ideas on this?

[lucassz]

@hdoupe According to my understanding of the Django documentation, it would indeed default to the TIME_ZONE in settings.py, in this case UTC. So the behavior is not changing -- wrapping it in make_aware is just doing explicitly what Django was doing implicitly (with a warning) in a way that's deprecated but supported to preserve backward compatibility.

[hdoupe]

Ok, that makes sense. Let's just leve the make_aware wrapper to be on the safe side. Is this ready to be merged?

[lucassz]

@hdoupe Yes. Plus it gets rid of the warnings since we're doing it explicitly, so the Travis output will be cleaner.

[hdoupe]

Very nice. Thanks for the contribution.