Some files are saved to bad path for non-ASCII project path

[danny0838]

Steps to reproduce:

1. Using WinHTTrack Website Copier 3.49-2, language preference: Chinese-Big5
2. Create a project with name like zh at path like C:\Users\UserName\Desktop\中文.
3. Capture whatever site.
4. A folder named C:\Users\UserName\Desktop\���� is generated, with files backblue.gif and fade.gif.