added pdf weights
Tweak indenting of the last commit

Also remove limit on the nunber of events to run over in MC.
Add ElectroWeakAnalysis/Utilities from cms-sw/cmssw

These packages are required for the PDF, FSR, and ISR weights that will
be used to calculate uncertainties.
Remove ZDefinitionWorkspace

The workspaces have been replaced by the tuples, so we no longer write
them.
Use TFileService for the Tuples

Hopefully the issues we had with TTrees and TFileService (to wit, a very
large number of ProcessIDs after hadding the files) have been fixed by
removing the RooDatasets.
Add information about running with PDFs
Add ZFinder/TrigEff

This script calculates the trigger efficiencies and scale factors.
Add R9 to ZFinderElectrons and Definitions
Add Regression and Smearing to MC
Break out different event weights

The "Natural MC Weight", that is the weight that is read in for each
event from the MC files, and the vertex reweighting weight are now
handled separately in the TTree.
Add weighted_counter histogram for MC
Add new Data/MC files to the x-sec tool
Update data and MC for Cross-check plotter
Add DY Binning to Cross Check Plots