nm_train live training class

[SamedVossberg]

• Added the nm_train file which opens a Pyside6 GUI to record training data and train classifier
• Added a disconnect method the lsl stream
• Added a jupyter notebook example for the Trainer class

[timonmerk]

wish list:

• write nm_db.py module which creates sqlite tabel in outpath if it doesn't exists
• add sqlite write function nm_db.write_features after feature computation in run method
• remove list aggregation
• add function in nm_db.py to write head of db as csv and option to read db as pd df
• return value of run method is pd dataframe of database
• replace nm_analysis read db as df instead csv file

-> read into option to load sqlite db in webframe

For the upper db changes it would be great to add them in a separate PR.

[timonmerk]

Closed now and adressed in issue #345