Pymatgen

* Massive update to abinit support. Note that pymatgen.io.abinitio has
been refactored to pymatgen.io.abinit. (Matteo, Setten)
* NwOutput now supports parsing of Hessian matrices (contributed by Xin
Chen)
* Gaussian support now has the ability to read potential energy surface
and electronic transitions computed with TD-DFT (Germain Salvato
Vallverdu)
* Bug fixes for CifWriter with symmetry.
* Bug fixes for surface generation and reactions.
* Monty requirement increased.

* Fix wrong U value for Ce and Eu.
* Properly handle empty multiline strings in Cif
* Add ability to get specific data in MPRester.get_entries. Make all get_entry
methods consistent in kwargs.

* Force conversion to an actual list in selective dynamics and velocities in
Poscar.
* fix small bug in BSPlotter (wrong ylim)
* Elastic tensor parsing in Outcar

* Fix scripts.

* Bug fixes for MPRester.
* Ensure correct monty version requirement in setup.py.

* Rudimentary PWSCF output reading.
* Fix ASE support.
* Support for WAVEDERF and reading multiple dielectricfunctions in vasprun.xml.
(Miguel Dias Costa)