Merge "Pass -yaml to ds builds to generate _book.yaml version of reference TOC." into mnc-mr-docs am: 5d8d511264 am: 6049306d8c am: c25a9b0104
am: 4569e9515c

* commit '4569e9515c651616f7e24f563b52de98fb4bf258':
  Pass -yaml to ds builds to generate _book.yaml version of reference TOC.

Change-Id: I83d230df7e8fb620ec9ea57621492261fbb236b7