KLFitter for all hadronic ttbb
Implementing a new method for running KLFitter in a recent release. We follow what has already bin don here: !30681 (closed)
The 'One Top' LLH has also been implemented.
In addition, the top-xaod has been modified to also store the sum of squared event weights in the metadata. Since this information is not saved prior to the derivation cuts, we only compute it for the processed events and then re-scale it by the ratio of the sum of all events' weights and the sume of the processed events weights. Some variables have been added to allow for this.