2016-2017-2018 run-dependent corrections

[lbenato]

The following items must be updated for 2017-2018 eras:

• Introduce switches like "is2016", "is2017", "is2018"
• Run-dependent global tag
• PU corrections to be recalculated
• Run-dependent trigger lists
• Run-dependent JEC
• Run-dependent JER smearing
• Run-dependent MET corrections/uncertainties
• Run-dependent CSV working points and uncertainty
• Run-dependent electron corrections/uncertainties
• Run-dependent photon corrections/uncertainties
• Run-dependent muon corrections/uncertainties
• Run-dependent tau corrections/uncertainties

[MelanieEich]

Introduce switches like "is2016", "is2017", "is2018" --> done
Run-dependent global tag--> done
PU corrections to be recalculated --> done
Run-dependent JEC --> done
Run-dependent JER smearing --> done
Run-dependent MET corrections/uncertainties --> done

To be checked:
Run-dependent trigger lists
Run-dependent CSV working points and uncertainty
Run-dependent electron corrections/uncertainties
Run-dependent photon corrections/uncertainties
Run-dependent muon corrections/uncertainties
Run-dependent tau corrections/uncertainties