Undefined name: BaseModel is defined on line 102 (#9)

* Undefined name: BaseModel is defined on line 102

% `flake8 . --count --select=E9,F63,F7,F82,Y --show-source --statistics`
```
./OpenGait/lib/modeling/base_model.py:27:1: F822 undefined name 'BasicModel' in __all__
__all__ = ['BasicModel']
^
1     F822 undefined name 'BasicModel' in __all__
1
```

* Fix typo discovered by codespell

lib/modeling/base_model.py

@@ -24,7 +24,7 @@ from utils import evaluation as eval_functions
 from utils import NoOp
 from utils import get_msg_mgr
 
-__all__ = ['BasicModel']
+__all__ = ['BaseModel']
 
 
 class MetaModel(metaclass=ABCMeta):
@@ -356,7 +356,7 @@ class BaseModel(MetaModel, nn.Module):
     @ staticmethod
     def run_train(model):
         '''
-            Accept the instace object(model) here, and then run the train loop handler.
+            Accept the instance object(model) here, and then run the train loop handler.
         '''
         for inputs in model.train_loader:
             ipts = model.inputs_pretreament(inputs)