Updating to latest masters

Deployed new service (447940eba611ef65f9d251b86c63345c26b7adb5):
* Don't use the writer as part of the renderTempDir.
* Validate 'writer' parameter before creating a job object.
* Remove stringified metabook from most log messages.

Change-Id: Ibeec0dcfbaa64b29f4de8c52cf746d865f869535
Merge branch 'master' into wmf-deploy

Change-Id: I8fcaf91268d58599232462b4d2f97be18f2ba4ce