Remove oslosphinx

[Andreas Scheuring]

Due to legal issues we need to remove the OpenStack logo from our RTD documenation. For more details see [1][2][3][4].

The alternative is to host the docs on openstack.org - details to be figured out on [2]

[1] https://www.openstack.org/brand
[2] https://docs.openstack.org/contributor-guide/vendor-drivers.html
[3] https://review.openstack.org/#/c/434292/
[4] https://specs.openstack.org/openstack/docs-specs/specs/kilo/move-driver-docs.html

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/435000

[Andreas Scheuring (andreas-scheuring)]

Andy discussed this with Anne Gentle and Alexandra Settle - we keep the RTD openstack design including the logo.

[OpenStack Infra (hudson-openstack)]

Change abandoned by Andreas Scheuring (<email address hidden>) on branch: master
Review: https://review.openstack.org/434992
Reason: Will not follow up that path for now - keep things as is on RTD

[OpenStack Infra (hudson-openstack)]

Change abandoned by Andreas Scheuring (<email address hidden>) on branch: master
Review: https://review.openstack.org/435000
Reason: Andy talked to the Docs team and for the current release we go with the RTD approach