remote.storage.outbound logger should include http response status and have consistent format

remote.storage.outbound logger prints useful outbound request information in a compact format.

One useful addition to the log message would be the response http status code. This can help detect remote problems more quickly, and can help infer what/why Nexus responded to an inbound request.

Additionally, the npm plugin should log outbound requests in the same format as other proxy repositories do.