Update `__all__` when renaming an imported variable/function/class

[lieryan]

Describe the bug A clear and concise description of what the bug is.

To Reproduce Steps to reproduce the behavior:

1. Code before refactoring:

# mod1.py
__all__ = ['old_name']

old_name = 1

# mod2.py
from mod1 import *
print(old_name) 

2. Describe the refactoring you want to do

Rename old_name to new_name

3. Expected code after refactoring:

# mod1.py
__all__ = ['new_name']

new_name = 1

# mod2.py
from mod1 import *
print(new_name) 

4. Describe the error or unexpected result that you are getting

The __all__ dictionary was left still using the old_name:

__all__ = ['old_name']

Editor information (please complete the following information):

• Rope version: 0.20.1