Currently some keystone installation guide docs are part of
general OpenStack-manuals. Migrating those docs to keystone
documentation so that they can be reviewed effectively by
keystone developers too.
Added installation guides for Ubuntu, openSUSE and
Red Hat Enterprise. The installation guides for Debian will
be added once they are complete in openstack-manuals.
Also changed the toctree structure in install-guides to
include directives so that all sections appear on one page
rather than just links.
Partial-Bug #1694460
Change-Id: I03aecfd1544b559a8fbd1ab11c5474145cff9ff9
Samriddhi Jain