Allow NiFi to hash specific attributes of a record

Create a processor for NiFi to read in a file of records through the Record Reader service and hash specific keys within the record. 

The processor will accept a comma delimited list of strings that would specify the keys to be hashed, as an attribute. If the keys specified are not present in a given record, the processor should continue without resulting in a failure. 

The processor will have a list of hashing algorithms to be applied to the record, as well as an optional salt. 

The hashed value will replace the current value stored for the given key then passed on to the Record Writer service.