less verbose output with option

I would love if there was an option to turn

```
⨯ doing this and that
  not ok 9 bla should be equivalent
    ---
      operator: deepEqual
      expected: |-
        [  ]
      actual: |-
        [ ... ]
      at: add (bla.js:49:5)
    ...
```

to just

```
⨯ doing this and that
  not ok 9 bla should be equivalent
```
