MET systematics update
This updates the default of the MET Systematics tool to the latest precision recommendations.
We have also taken the opportunity to implement a long-standing AMG request to fix the ScaleUp and ScaleDown systematics to the proper __1up and __1down syntax that the rest of the collaboration uses.
We'll arrange for documentation to be updated and an email to release the recommendation to the collaboration asap.
Edited by Maximilian J Swiatlowski