Proposal: Use httptrace to get advanced metrics and error messages

[djboris9]

Proposal

We should use httptrace for requests done by the kubenurse in order to get more advanced error details like DNS failures and statistics like time-to-first-byte.

Positive impact

We will log a little bit more on http errors and get new metrics from the requests. This allows users for easier debugging like #44, where only a http client error message is present and will get insights on different latencies.

Negative impact

There could be a small increase in log messages and metrics.

Notes

There is already httptrace included using prometheus framework but it needs to be extended.