Update core

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

diff --git a/core b/core
index 6dd4e46..bf0ebb5 160000 (submodule)
--- a/core
+++ b/core
@@ -1 +1 @@
-Subproject commit 6dd4e4616dcd9034c169f460dafed0a87091fec9
+Subproject commit bf0ebb51d77a061ae970a1303c6b1a6f614ef86b