mgr/diskprediction_local: Replaced old models and updated predictor.

mgr/diskprediction_local: Replaced old models and updated predictor.

ProphetStor models are replaced with in-house developed models.
Preprocessors are also stored in addition to the prediction models.
Objects are now stored using joblib instead of pickle, as recommended by
scikit-learn docs.

"manufacturer-specific" models are used instead of "best-feature-match"
models. i.e., instead of models being trained (presumably) just based on what
features are available, models have been trained for each manufacturer.
This is because of variation in meaning and availibility of SMART
attributes across manufacturers.

Updated config.json, requirements.txt, and DiskFailurePredictor for these changes.

Signed-off-by: Karanraj Chauhan <kachauha@redhat.com>