Skip list - empty directories

[Thany]

When "skip empty directories" is checked, a directory is still uploaded when it contains subdirectories with only skipped files. Like this:

- somedir (4 files, all skipped)
-- somesubdir1 (2 files, all skipped)
-- somesubdir2 (3 files, all skipped)

Then only "somedir" will be created on the ftp server, while I don't think it should be be created, since it's effectively empty.