Issue #657 - Call on_train_end after early stopping (#723)

Author: HarshSharma12

pytorch_lightning/trainer/training_loop.py

@@ -353,6 +353,7 @@ def train(self):
                 stop = should_stop and met_min_epochs
                 if stop:
                     self.main_progress_bar.close()
+                    model.on_train_end()
                     return
 
         self.main_progress_bar.close()