Be more explicit about what is returned by read_epochs_eeglab and read_epochs_kit about mne-python

[larsoner]

For now the easiest solution would be to say that the return type is BaseEpochs, which is nice because it is a documented type

[hoechenberger]

this problem affects many readers and I believe it has at least been brought up when we added some type hints not too long ago.

i agree with you that this should be improved.

parts of the class hierarchy would probably need to be revamped.

[nabilalibou]

A solution in the meantime to make sure the reader has all the keys needed to understand what's behind could be something like:

Returns:
   EpochsEEGLAB/EpochsKIT : instance of [BaseEpochs]
        EpochsEEGLAB/EpochsKIT object (subclass of [BaseEpochs])

And having a markdown box:

See also: 
   [mne.Epochs] Documentation of attributes and methods.