Add boostd pprof metrics to grafana dashboard

[kylehuntsman]

Adds pprof metrics for boostd to the grafana dashboard in the docker monitoring stack.

• Exposes port 1288, which the web server with the /metrics handler is running on
• Adds a scraping job of the boost:1288 addresss to the docker/monitoring/prometheus.yaml config
• Adds an example stat and the pprof stats to the grafana dashboard

Grafana Dashboard Updates

Fixes #772