Switch to use openstackdocstheme 1.11 for all documents and set it up following correctly. Change-Id: If312a985702b1b591d3ca7346c5349905b23a66a
html_last_updated_fmt option is interpreted as a byte string in python3, causing Sphinx build to break. This patch makes it utf-8 string. Change-Id: I5f529e5f15341e28b257cd42766e66390469d3f6 Closes-Bug:#1693670
Change-Id: Ie67aae021efc835d4a1fb5bbfffb8761ea41a3b4 Closes-Bug: #1667053