Modern Alerting Support for Kapacitor Lacking.

The documentation is insufficient to deploy and manage any useful Kapacitor instances with InfluxDB OSS 2.x.

There should be clear examples on
- Reading Data from Bucket
- Reading Data from One InfluxDB and Writing into a different InfluxDB instance
- Debug Kapacitor
- Use any single altering endpoint (no examples given)

##### Relevant URLs
- https://docs.influxdata.com/influxdb/v2/tools/kapacitor/

Start with the Kapacitor documentation at https://docs.influxdata.com/influxdb/v2/tools/kapacitor/ and identify the existing deployment and management guidance for InfluxDB OSS 2.x. Done means the documentation includes clear examples for reading from a bucket, transferring data between InfluxDB instances, debugging Kapacitor, and using an alerting endpoint.

Written by the indexing model from the issue text.