fixed "download folder" for folders containing spaces

Selecting "Download selected folder(s)" in the search results creates a new folder with the same name (for each selected folder) in the "complete" directory. Apparently the os::mkdir does a shell-like expansion on its argument, if the folder name contains spaces it only takes its first "word".
I added the option not to expand the path to os::mkdir and used this in destinationPath().
It is a bit ugly but it works :)