Add support for simple regex in urls

[julienc91]

Add the possibility to add urls like:

https://example.com/[0-9].jpg

The expected result is for the download manager to convert this url into 10 urls:

https://example.com/0.jpg
https://example.com/1.jpg
https://example.com/2.jpg
https://example.com/3.jpg
https://example.com/4.jpg
https://example.com/5.jpg
https://example.com/6.jpg
https://example.com/7.jpg
https://example.com/8.jpg
https://example.com/9.jpg