Main changes:

• Adds Histogram input handler.
  • A simple input handler that reads TH1s from ROOT files into a std::vector and serves them up upon request by index.
  • This is so that samples can be written that do not require tradition MC vector inputs but want to behave like normal samples and be handed input histograms.
  • The input format is like: "HISTO:bla1.root[histname1,histname2],bla2.root[histname3]" This input would then contain 3 histograms that could be retrieved in order. A sample using this input handler must know that it is and explicitly downcast the InputHandlerBase pointer that it recieves from the event manager.
  • Histograms can then be retrieved by the GetHistogram(size_t) or GetHistograms member methods.
• Fixes MiniBooNE AntiQE-Like data release that was missing a line.
• Tidies the nuissmear sample.
  • Adds more documentation to smearceptance.md
• Tidies and signficantly expands the Smear_SVDUnfold_Propagation_Osc sample.
  • Adds documentation to OscStudies.md