thread support
fix use of exo preds.
Merge branch 'master' of ssh://yap.git.sourceforge.net/gitroot/yap/yap-6.3
save/restore exo
Merge branch 'master' of ssh://git.dcc.fc.up.pt/yap-6.3
fix bad ints (obs from Mei).
fix hashing function.
new versions.
fix argv[0] discovery.
exo clause support
handle random on big ints (jan burse)
Merge branch 'master' of ssh://yap.git.sourceforge.net/gitroot/yap/yap-6.3
Put solver always as the first argument