Add Tracing to the REST Services

[salaboy]

We should be able to have OpenTracing integrated and how that needs to be configured for the app.
We should be able to describe how instrumentation can be added to spring boot projects.

https://knative.dev/docs/serving/accessing-traces/
https://knative.dev/docs/eventing/accessing-traces/

• install jeager operator (https://github.com/jaegertracing/jaeger-operator)
• Point knative traces to jaeger(https://docs.openshift.com/container-platform/4.3/jaeger/jaeger_config/serverless-jaeger-integration.html)

[salaboy]

This is now working with Jaeger and the Jaeger Operator.. not with Knative yet.