lib/stats: add history graphs for counters in debug browser.

- Use counters to record all sys stats.

- Show history graphs in counter's stat page.
  + Collect data from counter's three time series (1m, 10m, 1h).
  + Add javascript/css to render graphs with duration selectors.

- Minor improvements/fix:
  + Show stat name in all stat pages.
  + Add pretty print for TimeSeries data type.
  + Use the tail time (instead of the head time) for the start time of a time series.

It looks like this:
https://screenshot.googleplex.com/OyY3zCYekOn

Change-Id: I53b838c8470abe7ee76a3d460c4bea12cd1121e5
8 files changed
tree: 94a12f672d5a05d081c60576a440fd2f74c3627e
  1. cmd/
  2. examples/
  3. internal/
  4. lib/
  5. runtime/
  6. services/
  7. test/
  8. .gitignore
  9. AUTHORS
  10. CONTRIBUTING.md
  11. CONTRIBUTORS
  12. envvar.go
  13. envvar_test.go
  14. LICENSE
  15. PATENTS
  16. README.md
  17. VERSION
README.md

Vanadium

This repository contains a reference implementation of the Vanadium APIs.

Unlike the APIs in https://github.com/vanadium/go.v23, which promises to provide backward compatibility this repository makes no such promises.