- Set end_time to the end of the current day before queueing historical collection to allow put match and update existing queue item
- Set last_perf_capture_on to end time when no metrics were available to prevent constantly queueing the same historical range.

https://bugzilla.redhat.com/show_bug.cgi?id=1436034

The specs should test
* a single day (where the realtime queue item should have no end time)
* realtime over multiple days (where the older queue items are
  historical)
* multiple attempts to queue realtime metrics for a single object in the
  same 20-minute window

…gle realtime capture.