Add BluePyEfe to analysis tools

[rly]

BluePyEfe aims at easing the process of reading experimental recordings and extracting batches of electrical features from these recordings.

GitHub: https://github.com/BlueBrain/BluePyEfe
Docs: https://bluepyefe.readthedocs.io/en/latest/

I think this package focuses on processing of intracellular electrophysiology data. I cannot find any documentation on the ability to read NWB data with it, but there is an NWB reader and a mention in this paper.