Avro schema autoregistration

[arkadius]

Would be nice to be able to:
As a user I know which message I want to publish as an avro , e.g.:

{ foo: #input.intValue, bar: #input.decimalValue

, but haven't created topic yet and haven't added schema to it.

So I want to:

• use node avro-sink
• pick topic that haven't exists yet
• pick <new schema version> (because current empty schema mean <latest schema version>
• provide key/value
• run process

It should cause: new schema is added.

Confluent client support https://docs.confluent.io/current/schema-registry/schema_registry_tutorial.html#auto-schema-registration
(it is turned on be default so we also using it)
We should consider: how changes in existing parameters will break compatibility of current node