Fix suggested file name when saving dirplay playlist
The suggested name was identical to the complete path
of the played folder, with a slash at the end, which,
if accepted, resulted in a file called only ".m3u8"
being saved there.
In case the path contained one or more dots, the string
was also stripped of the last dot and all chars following it.
Use Playlist Catalogue as the destination folder instead,
and pick last path component as the file name.
Change-Id: Ia2b7f7ebca746613d650bbab6d7a62ca1106efc6