Improve design of make chaff popup

[banaagravrommel]

Describe the bug
Improve design of make chaff popup. It should be readable and pleasing to the user's perspective.

To Reproduce
Steps to reproduce the behavior:

1. Open the application
2. Click BleachBit Icon on the top right
3. Select Make Chaff

Expected behavior
Popup should be readable and pleasing to the user's perspective.

Screenshots
https://ibb.co/xhMr8Zn

Desktop (please complete the following information):

• OS: Windows 10
• BleachBit version 4.3.0

Additional context
Some things to add as well
-Percentage indicator on the progress bar
-Add abort button while making files is in progress

[az0]

I agree that the dialog should be improved, though it is not a top priority now. The dialog was maybe not changed since it was added in BleachBit 3.0.

I uploaded your image in case ibb.co later deletes it.