new regression versions
Merge remote-tracking branch 'nick/nckw-new-regression-7-and-8-TeV' into nckw-regression-7TeV-and-8TeV
1) Adding v8 weights for use with 7 TeV analysis
2) regressionVersion member added to PhotonAnaysis (and reductiondat)
to switch version of regression calculated during reduction
3) extraTags updated to use latest HybridGBR code
Merge pull request #169 from nucleosynthesis/nckw-regression-7TeV-and-8TeV

Conflicts:
	PhotonAnalysis/src/PhotonAnalysis.cc