Change WARN logs to INFO where needed

[mvandenburgh]

This is a prerequisite to configuring Sentry, since WARNING logs will set off an issue alert there.

We may want to go back through and figure out if some of these can be removed, or at least downgraded to DEBUG logs. But this change will at least allow us to hook up our deployment to Sentry without blowing it up with issues.

[BryonLewis]

I'll have to update my Scoring Parity PR after this. I may remove some of the MAX_BBOX stuff from the downloading tasks but will probably keep some number of images so that it makes some stuff easier while debugging locally.