Add a warning for when no model is loaded

modules/text_generation.py

@@ -124,6 +124,12 @@ def stop_everything_event():
 
 
 def generate_reply(question, state, eos_token=None, stopping_strings=[]):
+
+    if shared.model_name == 'None':
+        print("No model is loaded! Select one in the Model tab.")
+        yield formatted_outputs(question, shared.model_name)
+        return
+
     clear_torch_cache()
     seed = set_manual_seed(state['seed'])
     shared.stop_everything = False