Bump plugin API to 2.16.27

This is the latest released 2.16 version and matches the version in the
test Docker image.

Change-Id: Idc94741b589addcbcb03cdef57aea90b3da5f7ee

WORKSPACE

diff --git a/WORKSPACE b/WORKSPACE
index a5008c7..063d2cb 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -3,7 +3,7 @@
 load("//:bazlets.bzl", "load_bazlets")
 
 load_bazlets(
-    commit = "6c39deb06f58bb62162ccb6865964f531739f512",
+    commit = "0ccc066431ad7e88a5cd9e06000ce677de1116ee",
     #local_path = "/home/<user>/projects/bazlets",
 )