v2017.9.1

• Massive refactoring of PhaseDiagram. Now, PDAnalyzer is completely defunct
  and all analysis is carried out within PhaseDiagram itself, e.g.,
  pd.get_e_above_hull as opposed to PDAnalyzer(pd).get_e_above_hull.
• Refactoring of structure prediction. Now in
  pymatgen.analysis.structure_prediction.
• New core Spectrum object and associated pymatgen.vis.plotters.SpectrumPlotter.
• Parsing energies from gen_scfman module in Qchem 5 (Brandon Wood)
• Improvements to LAMMPSData, vasp IO.