libxml/libxslt as external dependencies

[Frederic Crozat <fcrozat mandriva com>]

Hi guys,

while preparing GNOME 2.20.0 release, I noticed we were lagging for
libxml2 and libxslt release, because Daniel is no longer uploading those
modules on ftp.gnome.org but prefers to keep them on xmlsoft.org, since
he considers libxml2 / libxslt to be lower lever than GNOME, like a part
of the OS.

I've discussed with him over irc and we agreed on the following :

-for 2.20.0, I've pushed latest version of libxml2 and libxslt on
ftp.gnome.org so we don't need to change anything so late in the process

-for 2.21.x, we switch libxml2 and libxslt as external dependencies and
use xmlsoft.org to grab those tarballs.

-- 
Frederic Crozat <fcrozat mandriva com>
Mandriva