Deletes idle periods for multiple meters.

• After deletion of an idle period, the meter will be active during that period.
• The meter id, start date and end date of each period have to match exactly with the period that has to be deleted.
• A meter can occur only once in the enrollment array.
• If no matching idle period can be found for one of the periods in the array, the entire message is discarded and a 404 error is returned, stating which period can't be found.
• No periods will be deleted, even if other periods in the same JSON are valid.