2012 changes

- Updated 8TeV datasets in DataSetInfo_8TeV.py, with corresponding cross-sections and numbers of events. Although the weights are not applied in the analysis, this file is read in plots scripts to weight the MC properly. For this to be possible, input files names were changed in inputFiles.py (now corresponding to dataset names).
- Switched to rho-corrected isolation for electrons. Hasn't switched to it for QCD estimation yet.
- Added new configuration files for 2012 data/MC.