Add Normalizer Callback (#631)

* add normalizer callback

* implement shift and scale parameters computation

* change name files normalizer data callback

* reduce tests

* fix documentation

* add NotImplementedError for PinaGraphDataset

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Co-authored-by: FilippoOlivo <filippo@filippoolivo.com>
Co-authored-by: giovanni <giovanni.canali98@yahoo.it>

pina/callback/__init__.py

@@ -5,8 +5,10 @@ __all__ = [
     "MetricTracker",
     "PINAProgressBar",
     "R3Refinement",
+    "NormalizerDataCallback",
 ]
 
 from .optimizer_callback import SwitchOptimizer
 from .processing_callback import MetricTracker, PINAProgressBar
 from .refinement import R3Refinement
+from .normalizer_data_callback import NormalizerDataCallback