[ML] Per detector data filtering

We've had a request to support per detector data filtering. Currently, we can configure filters at the job level, using an Elasticsearch query, but not per detector. Doing this in the job's data feed, and supporting the full Elasticsearch query DSL, would likely be a lot of work. A simpler approach would be to allow one to exclude data (not) matching specific categories. This could likely be achieved with an extension to job custom rules.