Displays - Timeplot - Show (heading) observations relative to reference (heading) sensor

The Problem:
Observation and computation results can be shown, but not in relation to each other.

• Example:
  Multiple heading sensors can be shown, but not in relation to the primary heading used. How are the other Heading/Gyro's sensors and Heading results (COG, Computed heading) relating to the object's / Vessel's primary heading/Gyro sensor?

Proposed Solution:
Add the option to:

1. Select a reference sensor
2. Show observations relative to the reference (Shows offset between sensors)

The QC report functionality already offer such option:
Go to Offline/Replay - Export - QC_Report

Heading Absolute	Heading Relative