Rivet info, b jet info, tau and trigger cleaning

[cecilecaillol]

• Added gen MET info from RivetAnalysis
• Added generated tautau decay mode
• Added generated dressed lepton information
• b jets sorted by btag score
• b jet information (including) JES for the first 2 b jets
• Added double lepton triggers and matching
• Removed outdated tau ID discriminators, deep tau ID moved from ztt.py to taus.py
• Removed unused triggers