add folder structure to select files in select-file option

[vitaminac]

add folder structure to select files in select-file option #76, and then we can make less clicks for select or unselect files, by making click in their parent folder input, that will apply same change to all subfolders and files inside it, useful when torrent file contains many files.

*folder
****subfolder
********file
****subfolder
********subfolder
********more subfolder... and so on
********file
********file
******** ...more files
*file
*file
..more files

[ziahamza]

Looks pretty good!!!! 💯 🕺

[ziahamza]

thanks @vitaminac !! <3

[vitaminac]

thank, it's my first pull request, i'm glad it can be accepted