Improve HTTP server logging

[samrushing]

The (new) HTTP server needs some improvements to how it logs. It needs to concentrate all logging into the request.done() method, and ensure that it is always called. Currently, there are sprinklings of log calls in several places, probably because of the error exit path. [for example, a connection reset will cause an exception in request.error() that keeps done() from ever being called]. This also means the format of the log line is unreliable and no information about bytes transferred is available on connections that have errors.