Use last core.

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

diff --git a/core b/core
index 38b7dbd..12ccfec 160000 (submodule)
--- a/core
+++ b/core
@@ -1 +1 @@
-Subproject commit 38b7dbd95e5d725eb2b7b34a6a8fe5e0c84073f0
+Subproject commit 12ccfec732e22546728674652a0a4caeeec08f60