Remove L0 related code
L0 is obsolete in Run3 and must be removed from master. It includes:
- Remove L0 event model classes
- Remove L0 and SPD/PRS from Calo code
- Remove L0 from Relation event classes
- Remove L0 functors
- Remove L0/SPD/PRS/PU decoder configuration (and obsolete configuration and tests)
- Remove pile-up decoding
Edited by Rosen Matev