* Update Tracer API with instrumentation version
Add option to the `Provider.Tracer` method to specify the
instrumentation version.
Update the global, noop, opentracing bridge, and default SDK
implementations.
This does not propagate the instrumentation library version to the
exported span. That is left for a follow-on PR.
* Revert trace_test.go
This is for the next PR.
* Support instrumentation library in SDK trace exports
* Update Jaeger exporter to export instrumentation