Filter aggregation result by result

## What?
It would be helpful to filter the displayed data by the result they have.
For example:
- We have a web server access log file.
- We want an aggregation showing the IP address and their time on our web server. (took_ms)
- To make the visualization a bit clearer we only want to display if the aggregated took_ms is
greater then say 3000ms. The rest we do not want to display.

Right now there is no way to filter out irrelevant data.

## Why?
If you display hundreds of IPs in your visualization the graphs can be quite small and cluttered with
a lot of small value ips which in sum might matter but not them alone. So the user would like to
filter these results.

## Your Environment

* Graylog Version:
* Elasticsearch Version:
* MongoDB Version:
* Operating System:
* Browser version: