Update README and setup.cfg, initial version of usage guide

* Set setup.cfg URL to the (future) documentation link
* Remove Python 3.3 and 3.4 support, leave only 3.5
* Update README with actual information
* Include README in index.rst as an introduction
* Very basic usage guide, mostly links to Tempest docs
* Switch links to HTTPS

Depends-On: If130b765604d606420a4877a548e82d311ef7b9b
Change-Id: Idacf84322773e40eaaa6346dc062291578876a1d
diff --git a/CONTRIBUTING.rst b/CONTRIBUTING.rst
index c0c5259..fa05b86 100644
--- a/CONTRIBUTING.rst
+++ b/CONTRIBUTING.rst
@@ -1,14 +1,14 @@
 If you would like to contribute to the development of OpenStack, you must
 follow the steps in this page:
 
-   http://docs.openstack.org/infra/manual/developers.html
+   https://docs.openstack.org/infra/manual/developers.html
 
 If you already have a good understanding of how the system works and your
 OpenStack accounts are set up, you can skip to the development workflow
 section of this documentation to learn how changes to OpenStack should be
 submitted for review via the Gerrit tool:
 
-   http://docs.openstack.org/infra/manual/developers.html#development-workflow
+   https://docs.openstack.org/infra/manual/developers.html#development-workflow
 
 Pull requests submitted through GitHub will be ignored.