## Is your feature request related to a problem?

A user mentioned needing a feature to clone dashboards as they create the same dashboard multiple times, each for a different end-customer. Given that we are already planning on doing default / custom dashboards (#1659) we can add this functionality to facilitate dashboard creation.

## Describe the solution you'd like

Simple functionality to duplicate a dashboard.
- Add "Duplicate" button to dashboard list and clone dashboard (e.g. "Copy - AARRR").
![screenshot](https://user-images.githubusercontent.com/5864173/93866745-fce46100-fcbf-11ea-8c96-b1acfb1981d5.png)


## Describe alternatives you've considered
Re-create the dashboard manually.


## Additional context
No additional context.


#### *Thank you* for your feature request – we love each and every one!

posthog/api/test/test_dashboard.py
dashboard = Dashboard.objects.create(team=self.team, share_token="testtoken", name="public dashboard")
        response = self.client.post(
            "/api/dashboard_item/",
            {
                "dashboard": dashboard.pk,
                "name": "dashboard item",
                "last_refresh": now(),  
            },
        )
        self.assertEqual(response.status_code, status.HTTP_201_CREATED)
        dashboard_item = DashboardItem.objects.get()
        self.assertEqual(dashboard_item.name, "dashboard item")
        
        self.assertRegex(dashboard_item.short_id, r"[0-9A-Za-z_-]{8}")
    def test_token_auth(self):