feature request: support avro serdes using schema registry

[brokenjacobs]

It would be great to support other serialization formats besides json. We use avro serialization with mqtt and bridge to kafka. Being able to visualize and display avro data would be huge for us.

It looks like this could be done using:
https://www.npmjs.com/package/avro-schema-registry
and
https://github.com/mtth/avsc

My javascript skills are nonexistent, but opening this as a PR in case someone with them could implement this.