[Tracker] Tracker and upcoming glib/gio: file monitoring

[Luca Ferretti <elle uca libero it>]

I've added a new bug[1] against tracker asking to use file system
monitoring features provided by glib/GIO.

Of course GIO is still under development, so Tracker can't yet depend on
it; but could be interesting check if the GIO API for file monitoring is
good for real usage and eventually report issues or requests to
developers.

PS maybe there are other GIO features that tracker can use, just use
your imagination :-)

[1] http://bugzilla.gnome.org/show_bug.cgi?id=507861