#2 Clarify doc

[Olivier Cailloux]

The old website (decision-deck.sourceforge.net) still exists and contains outdated or redundant doc.
1) Check with Raymond if he still needs the doc about d3. The main website (decision-deck.org) references the sourceforge one, the data should be taken from sourceforge.net to decision-deck.org instead to have everything in one place.
2) Check the outdated doc about old version to make sure there is nothing interesting there, move what's interesting to the D-D website.
3) Delete the old website (avoids confusion for people browsing there by chance).

[Olivier Cailloux]

... also check about the mailing lists. The rest of the old site can be deleted (I checked it).