[Feature request] Console commands to move last run screenshots for feature to reference or pending directory

As far as I see, working with reference and pending screenshots manually is tedious and can be automated.

What if we had a new CLI command, something like

```
zucchini approve /path/to/feature
zucchini approve --pending /path/to/feature
```

to move screenshots from the last successful run to the `reference` or `pending` directory?
What do you think?
