Enable Beeline to simultaneously accept w3c and honeycomb propagation headers

[bdarfler]

Is your feature request related to a problem? Please describe.

Currently, it's not possible to incrementally move a microservices architecture from the honeycomb propagation headers format to the w3c propagation headers format. This makes it difficult if not impossible for beeline customers with a large enough deployment to move towards interoperating with OpenTelemetry.

Describe the solution you'd like

Allow the beeline to simultaneously accept both w3c and honeycomb propagation headers, whichever is found on the incoming request. The outgoing propagation header format can still be static and set by configuration.

Describe alternatives you've considered

Additional context

[bdarfler]

This may require us to change the beeline id generation to always be w3c compatible (e.g 16 bytes in hex)