GTK+ DND tutorial updated

[Taura Milana <learfox furry ao net>]

http://wolfpack.twu.net/docs/gtkdnd/

The demo has been completely rewritten, it's been simplified
and uses the info data instead of iterating through the
target names list.

Lots of other fixes here and there too.

The DND drag action code has now been merged into the demo
for convience.

--
Sincerely,                  ,"-_                         \|/
-Capt. Taura M.             ,   O=__                    --X--
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                  http://furry.ao.net/~learfox/