Update Sizzle: improved dir caching

diff --git a/src/sizzle b/src/sizzle
index a99f6807bbf41ebd46bb9d044d53a664f371291c..3df37f8b4a3457bf5740d55bc73d5ab7e1357b36 160000 (submodule)
--- a/src/sizzle
+++ b/src/sizzle
@@ -1 +1 @@
-Subproject commit a99f6807bbf41ebd46bb9d044d53a664f371291c
+Subproject commit 3df37f8b4a3457bf5740d55bc73d5ab7e1357b36