* Extend storage service protobuf with TagKeys and TagValues
Co-authored-by: Michael Desa <mjdesa@gmail.com>
Co-authored-by: Jacob Marble <jacobmarble@influxdata.com>
* Extend the reads.Store interface with new TagKeys and TagValues APIs
* Extend readservice.store to implement refactored reads.Store interface
* Implement a StringIterator gRPC writer / serializer
* Implement a StringIterator gRPC reader / deserializer
* Implement a StringIterator merger