Update core

Signed-off-by: Florent Bruneau <florent.bruneau@polytechnique.org>

diff --git a/core b/core
index 47205c5..ddeb5f8 160000 (submodule)
--- a/core
+++ b/core
@@ -1 +1 @@
-Subproject commit 47205c58a02803a71bacb4c926207d81fbc18c13
+Subproject commit ddeb5f8915f2aed8877689b0db19a63791c4e57d