Add test on the header metadata key.
Add test on the header metadata key.

adamclifford/Wyam,Wyamio/Wyam,adamclifford/Wyam,adamclifford/Wyam,adamclifford/Wyam,heavenwing/Wyam,adamclifford/Wyam,Wyamio/Wyam,Wyamio/Wyam,heavenwing/Wyam