Nckw normalisation for signal from combine package

1) Python modules from CombinedLimit now used to calculate XS and BR as function of HiggsMass.
This is automatically done inside Normalisation_8TeV so no need to change interfaces to that
2) Signal type convention defined as follows:
  if typ=-1 in .dat file, signal type will be set as 1000*MH + 0 if ggh, 100 if vbf, 200 if WH ...etc
where MH and process are taken from 'Nam' and these are used then to calculate XS and BR.
(if typ==-1 but a corss-section is given, then the given x-section is used)

The old type convention is maintained in Normalisation_8TeV for back-compatibility and its us in PhotonAnalysis.cc

FIXME:
  Python scripts need to Load libHiggsAnalysisCombinedLimit.so to get imports to work (for using RooSpline1D) can this be fixed by editing the Makefile?