Pymatgen

* Completely revamped Compatibility/Correction system which improves
readability (Shyue Ping Ong/Anubhav Jain/Sai Jayaraman). This change is
backwards compatible for the most part.

* Big fix release for json dumping for unitized floats.

* Bug fix release to improve CIF parsing for more non-standard CIF files.
In particular, non-ascii characters are removed and \_cgraph\* fields are
removed prior to parsing for better support in PyCiFRW.

* Bug fix release. Incorrect units assigned for ionic radii.
* Improved nwchemio supports COSMO and ESP calculations (Nav Rajput).

* **Units**. Pymatgen now has a new system of managing units,
defined in pymatgen.core.units. Typical energy, length, time,
temperature and charge units are supported. Units subclass float,
which makes the usage transparent in all functions. The value that they
being are in terms of conversions between different units and addition and
subtraction of different units of the same type. Some basic quantities
like ionic radii and atomic masses are now returned in unitized forms for
easy conversion. Please see :mod:`pymatgen.core.units` and the
:doc:`examples </examples>` for a demonstration of house to use units in
pymatgen.
* **Minor backwards-incompatible change**. Structures are now sorted by
default when generating VASP input files using vaspio_set. Old behavior can
be obtained by setting sort_structure=False in the constructor. This is
typically the desired behavior and prevents the generation of large
POTCARs when atomic species are not grouped together.
* Bug fix for Molecule.substitute. Earlier algorithm was not detecting
terminal atoms properly.
* Additional conversion tools for ABINIT (by Matteo Giantomassi).

* Minor bug fix release to fix pyhull dependencies to be more friendly.
* Improved structure matcher that allows for more flexible matching. New
matching between ordered and disordered comparator.