MSG:
* Add addtionnal checkings on channel values in communicating functions.
+ GRAS:
+ * Actually implement gras_datadesc_copy() so that we don't have to mimick
+ RL communication on top of SG since it's so uneffective.
+ It may also be used for inter-thread communication in RL, one day. [MQ]
Documentation improvements:
* xbt_log module unmercifully reworked [MQ]