[Rlog27] Add replay capability

- Add support for replaying log files to the ResearchLogger.  This will let
  users preview data that they choose to upload.
- When the user explicitly requests that the system record their action, it
  will record everything up to, and including, the motion involved in shutting
  off the recording.  This change also removes the stop-recording motion
  commands.

Change-Id: Ib1df383bbf1881512cb111fab9f6749c25e436ba