Rework the old logo

* Re-work the old banner logo for the Sphinx docs
* Remove the remaining leftover assets from the old web site

So this is one possibility, I retained the other logo files so we have
options to play with.

Change-Id: Iac15899780072450dc30600a719283c0e2b0c0ae
Add NOVA_API_VERSIONS

This provides a mechanism for overriding v2 endpoint with v2.1 so that
tests can be run against a devstack to provide equivalency between the
APIs.

Change-Id: Iaaa530bda6bcdae75e86be8dbe572abe4396e8e9
Merge "Add NOVA_API_VERSIONS"
Fix NOVA_API_VERSION option

lib/nova checks NOVA_API_VERSION for setting Nova v2.1 API endpoint,
but the name of the initialization is different.
This patch fixes it.

Change-Id: I2fa234d66fe76b2a7146288adc1384b33921e178
Merge "Rework the old logo"
Merge "Fix NOVA_API_VERSION option"
Merge branch 'master' of https://github.com/openstack-dev/devstack