make gio the default instead of crufty old gnome-vfs

- distro-config for Linux should stay fine as it is explict about
  gnome-vfs
- this makes e.g. a:
    sudo apt-get build-dep libreoffice
    ./autogen.sh
  work out of the box for Ubuntu Quantal

Change-Id: I5a85f7af80f798a683e5c92b329ed3d4fd250a1f
Reviewed-on: https://gerrit.libreoffice.org/3114Reviewed-by: Michael Meeks <michael.meeks@suse.com>
Reviewed-by: Tomáš Chvátal <tchvatal@suse.cz>
Tested-by: Tomáš Chvátal <tchvatal@suse.cz>
Reviewed-by: Björn Michaelsen <bjoern.michaelsen@canonical.com>
Tested-by: Björn Michaelsen <bjoern.michaelsen@canonical.com>

configure.ac

@@ -923,12 +923,12 @@ AC_ARG_ENABLE(gnome-vfs,
     AS_HELP_STRING([--disable-gnome-vfs],
         [Determines whether to use the Gnome Virtual Filing System on platforms
          where that VFS is available.]),
-,enable_gnome_vfs=yes)
+,enable_gnome_vfs=no)
 
 AC_ARG_ENABLE(gio,
     AS_HELP_STRING([--enable-gio],
         [Determines whether to use the GIO support.]),
-,enable_gio=no)
+,enable_gio=yes)
 
 AC_ARG_ENABLE(telepathy,
     AS_HELP_STRING([--enable-telepathy],