ENH _mne:  source_induce_power()
ENH MneExperiment:  don't cache morph matrix (creation is quick)
ENH _mne:  add morph_source_space()
ENH MneExperiment:  load_evoked_freq()
ENH MneExperiment src:  add distances
ENH NDVar repr:  leaner __repr__, new .diminfo()
FIX NDVar:  UTS indexing error message
ENH NDVar:  Scalar indexing allow close value match