- Modify card covers/mini-cards so that:   1) Received date is shown unless there is a start date   2) Due Date is shown, unless there is an end date.
- Modify card covers/mini-cards so that:
  1) Received date is shown unless there is a start date
  2) Due Date is shown, unless there is an end date.

This begins to address #1668

Thanks to rjevnikar !

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