.desktop file: supported URL schemes key

[David Zeuthen]

Hi,

The GIO/GVfs behavior is described here:

 http://library.gnome.org/devel/gio/unstable/GAppInfo.html#GAppInfo.description

As you can see, GIO apps never ever pass URIs to apps if the URI is
available via a FUSE mount (virtually all interesting protocols such
as smb, sftp, ftp and so forth). Second, GIO apps will map things back
(thus avoiding FUSE). Third, at the same time non-GIO apps, such as
mplayer or VLC, works just fine (through FUSE).

Therefore, we actually don't have the problem in GNOME that you are
trying to solve.

Thanks,
David