Adding ScanJson
Adding Apache copyright
Add schema output toString
Add PhysicalOperatorIterator
Only send schema diffs, Single/Multi type List schema
Field has parent schema reference
Output proto schema (Maps only)
Output List schema and mixes
Add test around schema addition
Working Reference Interpreter.  Remove fake files.  Updates to common as reference interpreter clarified things.
Move jackson helper; Add more test
Move closer to RecordIterator interface
Adding main method. Match closer to RecordPointer and RecordIterator impl
Port ProtoTransformer to use DescriptorProto
Fix field removing and swapping
Fix rebase on execwork