Make sure that we won't try to reuse a socket closed by the user, even if we have...

Make sure that we won't try to reuse a socket closed by the user, even if we have dumb users closing sockets containing more buffered messages after the one being handled. Instead, we do a CRITICAL() and ignore the buffered message. Not optimal either, but hell, I don't have any better idea

git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/simgrid/simgrid/trunk@2786 48e7efb5-ca39-0410-a469-dd3cf9ba447f