Updates core.

diff --git a/core b/core
index 7f8e81b..f992b7a 160000 (submodule)
--- a/core
+++ b/core
@@ -1 +1 @@
-Subproject commit 7f8e81bbf66f2fe959e93f865fd74a08e20e9fee
+Subproject commit f992b7a5586a214d1704c9e74b7d1299e2c87a03