Eliminate `saveVariable` and `loadVariable` in `utils`
These functions are kind of useless wrappers for joblib.load
and joblib.dump
.
We should eliminate them and either pickle them directly or use load/dump.
Also keep in mind that sklearn.externals.joblib
has been deprecated (to be removed in 0.23),
so if we continue to use it we should explicitly depend on/import from joblib
.