Update core

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

diff --git a/core b/core
index b291bc1..aa2ac75 160000 (submodule)
--- a/core
+++ b/core
@@ -1 +1 @@
-Subproject commit b291bc172a649420710073c774de6b5470376d05
+Subproject commit aa2ac7586d7bb1e1479e65a0adef781395fdc57c