pymatgen preset in ElementProperty

[computron]

The features chosen for the "pymatgen" preset are somewhat random (I chose them on a whim, based on no data, while coding in a rush)

Someone can try to do a better job with this...

[computron]

Another thing one could do is:

• "pymatgen" preset just contains a large list of pymatgen element properties
• add a new "matminer" preset that tries to find all the independent columns between DEML, Magpie, pymatgen (i.e., columns that are not just linearly dependent on one another) and combine all those into one preset.