[Box Backup] Boxi 657 and Box Backup R2549 do not back up empty files

[Achim]

Boxi 657 (bug 2831965 [1]) and Box Backup R2549 (not ticket opened yet) do
not back up empty files

How to reproduce:
1. Create a new directory with the name "empty"
2. Inside the directory "empty", Right-click, choose "New" - "Text file"
3. Call the file "foo" and confirm the warning about changing the extension
4. Inside the directory "empty", create another directory "bar"
5. Inside the directory "bar", Right-click, choose "New" - "Text file"
6. Call the file "foobar" and confirm the warning about changing the
extension
7. Back up directory "empty" with boxi or bbackupd.exe
bbackupd.exe:
> NOTICE:  Finished scan of local files
> NOTICE:  File statistics: total file size uploaded 0, bytes already on
server 0, encoded size 0
In Boxi, already the "Total" file count is wrong: 2 instead of 4
8. Confirm that no file has been uploaded
query > ls -r
00000002 -d---- empty
00000003 -d---- empty/bar


but it should be (from the file system)

$ ls -lR empty/
empty/:
total 0
drwx------+ 2 achimlatz ???????? 0 Aug  4 13:52 bar
-rwx------+ 1 achimlatz ???????? 0 Aug  4 13:40 foo

empty/bar:
total 0
-rwx------+ 1 achimlatz ???????? 0 Aug  4 13:42 foobar

[1]
<https://sourceforge.net/tracker/?func=detail&aid=2831965&group_id=135105&atid=731482>