Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>

The issue is twofold:
- converting filenames that are already UTF8 encoded from the Qt dialog box
- missing UTF8-to-locale conversion for filename passed as parameter to vlc

These bugs accounted for skins with name or path containing multibyte
characters not being able to load successfully on Windows.

This fixes trac #14843

Since we have no real way to drain stream demux fifo,
we should have a way to reset demuxer before switching to
a new segment.

Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>

libvlc: expand media player API to retrieve full information about available chapter of a given title

libvlc: expand media player API to retrieve information about all available titles of the currently playing media item