message: Improve `nctl-metrics` `README.md`
diff: # Metrics for nctl
  -A small setup that runs enough containers to get metrics working when using nctl. Contains
  -
  -* a python script that will scrape memory metrics from the OS and make them available via HTTP for prometheus,
  -* a generator for a prometheus configuration file based on current nctl assets (only `net-1` supported), and
  -* a supervisord configuration to run the generator and prometheus conveniently.
  +A small setup that runs enough containers to get metrics working when using nctl.
  ## How to run
  1. Ensure nctl has generated assets (`nctl-assets-setup`).
  2. Run `supervisord -c utils/nctl-metrics/supervisord.conf`.
  -3. Navigate to localhost:9090 and watch metrics.
  +3. Navigate to <http://localhost:9090> and watch metrics.
  +
  +## Architecture
  +
  +The directory contains
  +
  +* a python script that will scrape memory metrics from the OS and make them available via HTTP for prometheus,
  +* a generator for a prometheus configuration file based on current nctl assets (only `net-1` supported), and
  +* a supervisord configuration to run the generator and prometheus conveniently.
  ## Metrics offered
  