Update bazlets for Bazel 0.5.1

Change-Id: I2f496662aa58ca743e7b9c626ae3e6bc90df8ef0
diff --git a/WORKSPACE b/WORKSPACE
index ebfb757..9463f1a 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -3,7 +3,7 @@
 load("//tools:bazlets.bzl", "load_bazlets")
 
 load_bazlets(
-    commit = "42244973783cd0b14c5dc24014a97c4148488d6a",
+    commit = "680d42de63b146e77d41685b38a295abb2980b6d",
     # local_path = "/home/<user>/projects/bazlets",
 )