+ Introduce the SIMIX module: factorize code between MSG and GRAS.
+ [Bruno Donassolo]
+ 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) and speed
+ up simulations by to 40% (even if it were not the main goal).
+
+ **************************************
+ *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 in
+ some cases. Sorry for the inconvenience.
+
+ Overall changes:
+ * Make the backtrace of exceptions more human readable [Mt]