L0calo GEP pileup subtraction and template jet/MET algorithms

First implementation of calorimeter based algorithms for the GEP. The project is a phase II project, but to synchronize code between 21.3 and 21.9, we prefer to sweep from 21.3->21.9. The developments are also useful for Run 3 HLT. Here we include:

• Clusters with SK removal scheme
• Clusters with subtraction based on Voronoi areas
• Clusters with subtraction based on Voronoi areas followed by soft killer
• Pileup fit subtraction of towers.
• A template algorithm to implement cluster timing cuts

All algorithms are based on the offline/HLT, and additional evolution will be required to match the actual GEP firmware.

We also include implementation of the following objects:

• Calorimeter jets with each set of input clusters
• Calorimeter MET

Outputs are saved into storegate as xAOD containers. The current job setup can run for AOD/ESD or any input with clusters. The default EDM is not changed, so the containers need to be persistified with Reco_tf job options of desired.