Upgrade bazlets to get adaptations for bazel 0.6

In bazel 0.6 the set() method is deprecated in favor of depset().

Update bazlets to get the necessary rule updates.

Change-Id: I1d21b422899791bf491a8eb1e43bbe0bba91d1bd
diff --git a/WORKSPACE b/WORKSPACE
index 5085997..1122bcf 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -3,7 +3,7 @@
 load("//tools:bazlets.bzl", "load_bazlets")
 
 load_bazlets(
-    commit = "a615d69786a965e9622761ff2229446115732cca",
+    commit = "c183e91a343af59e7bb021c19fee62a1dc6ea6ce",
     # local_path = "/home/<user>/projects/bazlets",
 )