- adds Spring Cloud Function instrumentation
- adds Operators to manually provide instrumentation for Fluxes
- introduces Manual instrumentation mode for Reactor
TODO: Documentation (will add it soon)
related gh-1684
Brave's SpanHandler can report natively in other formats which have different
constraints than Zipkin and often extensions to the data model.
This change ports all tests away from Zipkin's types so that it is more clear
what's actually recorded vs what's a side-effect of Zipkin conversion.
This removes `BlockingQueueSpanReporter` which was never released, also.
