[ENH][Channel Selection] Riemannian based channel selection #31
Description
https://ieeexplore.ieee.org/document/5910558
https://ieeexplore.ieee.org/document/9313336
Utilises distance measures between covariance matricies for each class to identify and remove least disciminatory channels. Other distance measures can be used but Riemannian distance was considered the best.