feat: added error message when attempting a wrong login

run.py

@@ -144,6 +144,11 @@ You can log in to your character typing:
                             add_player(id, name, pl["species"], pl["description"], pl["room"])
                             waitlist.pop(id)
                             break
+                    else:
+                        found = False
+                        for name, pl in characters.items():
+                            if params_list[0] == name: found = True
+                        if not found: mud.send_message(id, "Character '{}' not found".format(params_list[0]))
 
             else:
                 mud.send_message(id, "Unknown command " + command)