set
  Adds data to the SelfDescribingJson
- Accepts a TrackerPayload object 
Return
itself
Parameters
tracker
the data to be added to the SelfDescribingJson
Adds data to the SelfDescribingJson
- Accepts a POJO 
Return
itself
Parameters
data
the data to be added to the SelfDescribingJson
Allows us to add data from one SelfDescribingJson into another without copying over the Schema.
Return
itself
Parameters
self
the payload to add to the SelfDescribingJson