WIP ENH MneExperiment:  use Python based source space and forward solution generation
WIP FIX:  MneExperiment.load_epochs_stc()
WIP ENH MneExperiment:  has_edf option
ENH MneExperiment.make_labels():  automatically make labels for common_brain
FIX MneExperiment.make_labels()
ENH MneExperiment:  auto-make source space
ENH Mne-Experiment:  threshold only `rej` option