removed the obsolete simple parameters class and all of its references
moved Avro conditions into the Avro decoder
added a new JSON transcoding trait
refactored the Avro decoder
refactored I/O sources
added JSON transcoding logic
Nil is simpler than Seq.empty
Avro decoding moved from support packages
added a new command to find the next message matching a condition
added basic support for complex conditions
all Kafka message retrieval functions now support JSON output
updated examples to include JSON output and complex queries