Traces: Use OpenTelemetry

[refs]

What is OpenTelemetry?

• open standard
• sandbox CNCF project.
• formed through a merger of the OpenTracing and OpenCensus.

OpenCensus and OpenTracing have merged to form OpenTelemetry, which serves as the next major version of OpenCensus and OpenTracing. OpenTelemetry will offer backwards compatibility with existing OpenCensus integrations, and we will continue to make security patches to existing OpenCensus libraries for two years.

There is a lot of outdated documentation as a result of this merger, and we think adopting the latest standard and libraries will benefit the project.

[update-docs]

Thanks for opening this pull request! The maintainers of this repository would appreciate it if you would create a changelog item based on your changes.

[refs]

@labkode @ishank011 does it make sense I update all traces occurrences that use the go.opencensus.io lib? I see the EOS storage provider binary is rich with traces and metrics, we could tackle that in this PR or in a follow-up one. How does that sound?

There are still a few technicalities to solve, but I'd say this PR is in good track.

[labkode]

Hi @refs, yes we can take the EOS part later. I think we should go for OT as default.

[refs]

@labkode I think the current state should be ready for review. However I still need to wrap my head around the metrics instrumentation.

This PR should leave the traces in a better state than they currently are.