+ Introduce the SIMIX module: factorize code between MSG and GRAS.
+ Until now, GRAS were using MSG as an interface to SURF. It was
+ quite difficult because both interface have several differences
+ (MSG channels vs GRAS sockets were the most notable point).
+ This also opens the gate to SMPI, which should occur soon.
+
+ DO NOT MIX 3.2 RESULTS WITH 3.3 ONES: Simix may changes simulations
+ The point is that events occuring at the exact same timestamp are
+ not scheduled in the same order with the old and new version. This
+ may be enough to completely change the execution of simulations.
+ Sorry for the inconvenience.
+