## Is your feature request related to a problem?

I want to be able to download a CSV of users when I click on a datapoint in a graph

## Describe the solution you'd like

![image](https://user-images.githubusercontent.com/1727427/114418453-cd8d3700-9bb2-11eb-906d-8aa424f48500.png)

When I click on a datapoint I'd like to be able to download a CSV as well as create a cohort from it.

## Describe alternatives you've considered



## Additional context



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

posthog/api/action.py
queryset = queryset.annotate(count=Count(TREND_FILTER_TYPE_EVENTS))
    queryset = queryset.prefetch_related(Prefetch("steps", queryset=ActionStep.objects.order_by("id")))
    return queryset.filter(team_id=team_id).order_by("-id")
class ActionViewSet(StructuredViewSetMixin, viewsets.ModelViewSet):
    queryset = Action.objects.all()
    serializer_class = ActionSerializer
    authentication_classes = [
        TemporaryTokenAuthentication,
        PersonalAPIKeyAuthentication,
        authentication.SessionAuthentication,
        authentication.BasicAuthentication,
    ]
    permission_classes = [IsAuthenticated, ProjectMembershipNecessaryPermissions]
    def get_queryset(self):
        queryset = super().get_queryset()
        if self.action == "list":
            queryset = queryset.filter(deleted=False)
        return get_actions(queryset, self.request.GET.dict(), self.team_id)
    def list(self, request: request.Request, *args: Any, **kwargs: Any) -> Response:
        actions = self.get_queryset()
        actions_list: List[Dict[Any, Any]] = self.serializer_class(actions, many=True, context={"request": request}).data  
        if request.GET.get("include_count", False):
            actions_list.sort(key=lambda action: action.get("count", action["id"]), reverse=True)
        return Response({"results": actions_list})
    @action(methods=["GET"], detail=False)
    def trends(self, request: request.Request, *args: Any, **kwargs: Any) -> Response: