First set of 2016 upgrades
- Only 1 reclustering for Zinv: remove (loose) photons if Nμ=Ne=0, otherwise remove leptons
- Keep photon property branches only for IdIsoLoose photons
- Optimize some calculations of track-related variables
- Remove obsolete producers (old tagandprobe stuff, etc.)
- Move all producers to consumes (necessary for 7_6_X and above)