Add canary nightly build job

Bug: translateselectedtext:10
Change-Id: I77cfaaa048a1e6a388b1d120b7070f3fa32ae632
diff --git a/playbooks/nightly-build/post.yaml b/playbooks/nightly-build/post.yaml
new file mode 100644
index 0000000..5cb8988
--- /dev/null
+++ b/playbooks/nightly-build/post.yaml
@@ -0,0 +1,4 @@
+- name: Get CWS upload/publish log
+  hosts: all
+  roles:
+    - fetch-cws-log