Admin reports: Render precise values for totals in detailed reports
Record submissions for comments added from update_store command

Fix #3376
Reports: replace date with datetime in Paidtasks

- Change `date` PaidTask field to `datetime`;
- List paid tasks in Detailed Statistics.
- Show dates in ‘Registered tasks’ table in Admin/Reports and Statistics;
Reports: fix date interval when time was changed to (or from) DST
Reports: allow to add corrections as paid tasks

- Change amount field from positive integer to float;
- Add new paid task type;
- Use enum type instead of unnamed constants;
Reports: Clear effective_from field after user rates updating
Skip rqworker cache missed errors in DEBUG mode