Update requirements and code for python3, this will not work with
Also, update to openstackdocstheme as current OpenStack theme and
Some noteworthy changes:
* Remove reload, setting of UTF-8 in vmt.py - this is not needed anymore
* Update requirements of Sphinx to current versions
* The Markup construct does not work with python3 in conf.py, replace
with simpler string.
* No need to use "pip -U", remove -U option.
* in vmt.py: Strings are unicode in python3, no need to check for it.
Prepare for repository publication by:
- moving all YAML under ossa/
- cargo-culting doc building from openstack/governance
- adding a LICENSE (CC 3.0 BY)