crypt: implement DirChangeNotify
crypt: implement DirChangeNotify

crypt now implements the DirChangeNotify if the wrapped FS provides it.

seuffert/rclone,B4dM4n/rclone,seuffert/rclone,B4dM4n/rclone,seuffert/rclone,olihey/rclone,yonjah/rclone,yonjah/rclone,yonjah/rclone,B4dM4n/rclone,ncw/rclone,ncw/rclone,olihey/rclone,seuffert/rclone,B4dM4n/rclone,olihey/rclone,yonjah/rclone,ncw/rclone,ncw/rclone,olihey/rclone