[densenet] adding drop_rate in model params

The modified definition of the densenet model allows the user to pass a dropout rate in the model's constructor. The default dorp-rate is set to 0.1.

src/mednet/config/models/densenet.py

@@ -19,6 +19,7 @@ model = Densenet(
     validation_loss=BCEWithLogitsLoss(),
     optimizer_type=Adam,
     optimizer_arguments=dict(lr=0.0001),
-    augmentation_transforms=[ElasticDeformation(p=0.8)],
+    augmentation_transforms=[ElasticDeformation(p=0.2)],
     pretrained=False,
+    dropout=0.1,
 )