STY:  remove __hide__
FIX WxTerm:  don't use class variables on Shell
ENH datasets:  add MNE loader
TEST mne source space connectivity
ENH TreeModel:  incorporate .exclude
ENH FileTree:  ADD .rename_field()
ENH FileTree:  exclude parameter defaults (False in file operations)
FIX FileTree.get():  raise exception if make=True and no make handler is specified
ENH MneExperiment:  ADD .make_mov_ga_dspm()
ENH MneExperiment.load_inv():  don't require fiff file as input
ENH MneExperiment:  don't cache morph matrix (creation is quick)
ENH MneExperiment src:  add distances
FIX MneExperiment:  get("x-dir", make=True) creates directory
MOD MneExperiment:  don't set_env() on __init__