add a link to opentelemetry instrumentation

Signed-off-by: Mark Sagi-Kazar <mark.sagikazar@gmail.com>

tracing/README.md

@@ -30,6 +30,12 @@ not limited to Zipkin, Prometheus, Stackdriver Trace & Monitoring, Jaeger,
 AWS X-Ray and Datadog. Go kit uses the [opencensus-go] implementation to power
 its middlewares.
 
+## OpenTelemetry
+
+[OpenTelemetry] came to life as a result of merging [OpenCensus] and [OpenTracing].
+Go kit instrumentation can be found in [opentelemetry-go-contrib]
+which is a central repository of instrumentation libraries.
+
 ## OpenTracing
 
 Go kit supports the [OpenTracing] API and uses the [opentracing-go] package to
@@ -84,3 +90,6 @@ OpenTracing interface and are highlighted in the [addsvc] example.
 
 [OpenCensus]: https://opencensus.io/
 [opencensus-go]: https://github.com/census-instrumentation/opencensus-go
+
+[OpenTelemetry]: https://opentelemetry.io/
+[opentelemetry-go-contrib]: https://github.com/open-telemetry/opentelemetry-go-contrib