DEPR: Add deprecated index attribute names to deprecation list
In ipython, when you press tab (e.g. ``idx.<tab>``) a long list of deprecations shows up:

```
C:\Users\TP\Miniconda3\envs\pandas-dev\lib\site-packages\jedi\evaluate\compiled\__init__.py:328: FutureWarning: Int64Index.base is deprecated and will be removed in a future version
  getattr(obj, name)
C:\Users\TP\Miniconda3\envs\pandas-dev\lib\site-packages\jedi\evaluate\compiled\__init__.py:328: FutureWarning: Int64Index.data is deprecated and will be removed in a future version
  getattr(obj, name)
C:\Users\TP\Miniconda3\envs\pandas-dev\lib\site-packages\jedi\evaluate\compiled\__init__.py:328: FutureWarning: Int64Index.flags is deprecated and will be removed in a future version
  getattr(obj, name)
C:\Users\TP\Miniconda3\envs\pandas-dev\lib\site-packages\jedi\evaluate\compiled\__init__.py:328: FutureWarning: Int64Index.itemsize is deprecated and will be removed in a future version
  getattr(obj, name)
C:\Users\TP\Miniconda3\envs\pandas-dev\lib\site-packages\jedi\evaluate\compiled\__init__.py:328: FutureWarning: Int64Index.strides is deprecated and will be removed in a future version
  getattr(obj, name)
```

With this PR we avoid getting that list of deprecations in iPython.

I'm not sure if/where this should go in the whatsnew document.