Before this change we lowercased the dropbox root directory. This was
likely a leftover from when we used to build a dictionary to translate
the cases of dropbox files. Now with the v2 API we can rely on
dropbox to do that for us, so we no longer need to lowercase the root.
This fixes issues using crypt with name obfuscation on dropbox.
This is a problem when syncing a file which just needed its modtime
set with dropbox which can't set the mod time of a file without
re-uploading it.
Before this change we would delete the file, then the server side move
would fail moving the file to the backup-dir because it no longer
existed.
After this change the destination file is moved to the backup-dir
instead of being deleted and the new file is uploaded.
Fixes#2134
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.