Start adding error annotation

[marcingrzejszczak]

With Zipkin 1.3 https://github.com/openzipkin/zipkin/releases/tag/1.3.0 and openzipkin/zipkin#1140 error annotations can be resolved into a nice visualization in the UI.

[codefromthecrypt]

here's some hints here openzipkin/openzipkin.github.io#52

main thing is that we shouldn't have a span dangling (ex only cr) as the span detail tab looks off.