[FIX] doc: branch name in configuration

The branch name is used in the version switcher, so the master branch should have a version of "master".

Maybe the release could be the revision hash? Not sure how to extract it from the repo.
[FIX] website_sale: checkout: do not reset address country every time

Once the value is set it can be modified by the user
(e.g. if geoip detection was wrong), so should not be reset.
[REVERT] typo
Merge branch '8.0' of https://github.com/odoo/odoo into 8.0-win32