Sentry: off by one error in dates

[lukaszachy]

In did last week --sentry
Did says Status report for the last week (2018-09-10 to 2018-09-16)
but sentry plugin is doing query for Date range 2018-09-10 - 2018-09-17

Problem is that sentry is reporting back issue I commented on 2018-09-17

[psss]

Yes, the date ranges are a bit confusing. This is another real-life example confirming #60. We should fix that to make it more intuitive.