Improve API Error output

Currently, we just log the error directly. e.g.: `time="2018-12-04T12:57:26+01:00" level=error msg="[POST /api/v1/guids][401] createGuidUnauthorized  &{Code:0xc0001f8050 ErrorID:0xc0001f8080 ErrorList:[] Message:0xc0001f8060}"`		

We should log a JSON representation of the API error as well as all request parameters and headers.