**Problem:**
We are tracking the number of editors who make at least 1/5/100 edits in the past 30 days at https://grafana.wikimedia.org/d/000000162/wikidata-site-stats?orgId=1. This is for all edits across all namespaces. It'd be useful to also keep this statistic split by namespace. The main namespace, Property namespace and the Lexeme namespace are of special interest but we will want to look at the others as well.
**Acceptance criteria:**
[ ] new graph exists on https://grafana.wikimedia.org/d/000000162/wikidata-site-stats?orgId=1 that shows the number of editors per namespace over time
[ ] graph is split by activity level (at least 1/5/100 edits in the past 30 days)
**Notes:**
* We count only the edits an editor makes in a specific namespace. If they also edit in another namespace those edits are not counted into the number of edits for that namespace.
**Links that may be useful**
* https://github.com/wikimedia/analytics-wmde-scripts/blob/master/src/wikidata/site_stats/active_users.php
* https://github.com/wikimedia/analytics-wmde-scripts/blob/master/src/wikidata/site_stats/sql/active_user_changes.sql