Deletes a folder.
By default, will only delete empty folders.
If recursive=true, will delete the folder and all its contents (subfolders and projects).
Recursive deletion is asynchronous which means that while all relevant children will become inaccessible immediately,
only the parent folder will emit removal event. All clients need to assume all children are deleted based on that
top level notification.
If recursive=false, will only delete the folder if it is empty, erroring otherwise.