Use last version of core.

Signed-off-by: Vincent Zanotti <vincent.zanotti@polytechnique.org>

diff --git a/core b/core
index 6f84e15..029135c 160000 (submodule)
--- a/core
+++ b/core
@@ -1 +1 @@
-Subproject commit 6f84e151da62e6c48392658e0246508bea9e950e
+Subproject commit 029135c8d7891915fb00fdc5352ba57dc5fa2837