Fixed: goal cycle end dates

Previously, the time of an end date of a goal cycle (e.g. March 31 as the end of Q1) was set to 00:00:00, i.e. March 31st 00:00:01 was counted as being outside of the cycle Q1, showing Q1 as an inactive cycle (although it was still one day left). This is now fixed.

Furthermore, we adjusted existing goal cycle end dates that worked around this issue, as follows:

• All goal cycles ending on a 1st of a month, now end on the last day of the previous month at 23:59:59.
• All goal cycles that do not end on a 1st of a month, keep their date but end at 23:59:59.