add process.hrtime

[nichady]

[dop251]

Thanks for the submission.

process.hrtime is supposed to work with monotonic clock. In Go there is no direct access to monotonic clock, it's hidden in time.Time returned by time.Now() and then used when calculating difference between two such values.

However, you can try using a similar approach as here: https://github.com/juju/clock/blob/master/monotonic/monotonic.go