UI should explain first step

[alxndr]

I see this when first starting upgrade.py:

Replace:

    '.close\('  with  '.destroy('

[y,n,q] _

Based on the readme, I expected to see a diff with some context and a file name and line number. Instead I think this is going to blanket-replace all instances of .close( with .destroy(, which I don't actually want to do.

It would be nice if the UI explained that I am selecting whether or not I want to attempt to replace any calls of .close( with .destroy(.