ENH MneExperiment:  load_evoked_freq()
ENH MneExperiment movie: allow p0=0.1
ENH MneExperiment:  `all!` group
FIX MneExperiment:  `src-file` pattern needs to include "{src}"
WIP:  Volume source space
WIP ENH testnd:  test repr (add mintime etc.)
OPT stats:  _t_rel
WIP t-contrast
API cluster tests:  default pmin=0.05
WIP OPT _t_rel
WIP DOC _mne
OPT _Effect.sort_idx()
ENH Interaction: as_effects -> LazyProperty
ENH plot.brain:  ADD copy()
ENH fmtxt HTML:  embed images