delete files by pressing 'd' in the ncdu listing
GUI Improvements:
Boxes now have a border around them
Boxes can ask questions and allow the selection of options. The
selected option will be given to the UI.boxMenuHandler function.
Fixes#2571
Remove files/directories from the in memory structs of the cloud
directory. Size and Count will be recalculated and populated upwards
to the parent directories.
The purpose of this is to make it easier to maintain and eventually to
allow the rclone backends to be re-used in other projects without
having to use the rclone configuration system.
The new code layout is documented in CONTRIBUTING.
