Move datadesc and TCP sockets from GRAS to XBT.
XBT supports sockets with explicit choice of the transport plugin.
XBT provides only one transport plugin: TCP (i.e. real sockets) and
allows other layers to write their custom plugins.
GRAS implements such custom plugins: simulated sockets and file sockets.
TCP sockets only existed in GRAS RL mode. They can now also be used in
GRAS SG mode.
More pieces of GRAS remain to be moved to XBT before TCP sockets can
also be used outside GRAS (e.g. in SIMIX 3, one day, to distribute the
simulation).
- [D] teshsuite/gras/README