AT: Rework & clean up application of lepton/photon isolation tools

An overhaul of how isolation selection tools are used in AnalysisTop:

• Previously-hardcoded list of WPs is removed, every WP to be initialized should be specified via config options: ElectronIsolationWPs,MuonIsolationWPs,PhotonIsolationWPs.
• Configured WP decisions will be stored in aux decorations as was done until now
• The buggy workaround for missing isolation variables in derivations is completely removed, now users will get a crash with the missing variable name, if the WP they specified cannot be used on the derivation
• The old Electron/Muon/PhotonIsolation(Loose) configuration options still exist, and are used for selection decision for tight and loose lepton shallow copies