Drop tests of the transport layer. The introduction of the receiving thread make...

Drop tests of the transport layer. The introduction of the receiving thread make them impossible since this dude absolutely expects messages on the socket, and make impossible to exchange raw data as done in these tests. These functionnalities are well tested elsewhere. datadesc_usage tests file sockets, and pretty everyone tests regular sockets

git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/simgrid/simgrid/trunk@4604 48e7efb5-ca39-0410-a469-dd3cf9ba447f