Support for soft deleted models

[miloandco]

As far as I can see, it is not possible (when using Laravel Models) to filter on soft deletes.

For example, one month can have 10 new users created, but also have 3 users deleted. Then it would be useful to be able to somehow get a total of 10-3=7. Currently total would show up as 10, which can be both right or wrong, depending on your goal.

options([
  'withTrashed' => true, // Adds soft deleted rows to the result
  'onlyTrashed' => true, // Only soft deleted rows
  'calculateTotalAsNet' => true, // Subtracts soft deleted rows from total
])

Is this currently possible? Otherwise, it would make sense to add it to add some new options as displayed above. I can make a PR on it if anyone else needs it too.