p2p: support Prometheus histogram and summary metric types

[algorandskiy]

Histogram should cover OpenCensus's distribution type as well.

There is a relevant comment fro the p2p feature PR :
Maybe in a follow-up PR, I think we would want to report _count and _sum for each distribution so we can use it to get the average, and I think both would be reported as a prom counter type instead of a gauge type (so Grafana knows it can derive it over time to get a rate)

Originally posted by @cce in #5939 (comment)