Reconciliation adjustments

Even with the new Reconciliation Date field, doing reconciliation with Reconciliation Date being different from the Entry Date is still very difficult to do because of two little details:

1. The balance field is based on the Entry Date instead of the Reconciliation Date. Because of this, having entries sorted by Reconciliation Date results in a Balance column that makes no sense. When being in Reconciliation mode, the running balance should be based on the reconciliation date. (additionally, the reconciliation date column should be shown if it wasn't already, and it should be set as the sorted column)

2. Sorting of unreconciled entries when sorting by Reconciliation Date is weird (they all are at the beginning of the table), making it hard to do reconciliation because as soon as you reconcile an entry, it disappears. To fix this, unreconciled entries should fall back to their entry value as a sorting value.