[Feature Request] Convert into cbz

[djidane535]

We can save pages into jpg one by one. It would be nice to be able to save the whole comic in one click, and put all the jpg images into a cbz archive.

Also, having more control on the image quality would nice as well.

At the moment, I use YACReader to import some comics on my ereader, but I have to do it manually page by page, which is a bit cumbersome.