typos in readme.rst
typos in readme.rst

  Attempting to fix some minor typos in the
  readme.rst file.

  Closes-Bug: #1281408

Change-Id: I567c9cede5bb9548e2e87b48eb7f4eec8921953b

kairoaraujo/openstack-manuals,openstack/openstack-manuals,gongysh2004/openstack-manual,AlekhyaMallina-Vedams/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,openstack/openstack-manuals,potsmaster/openstack-manuals,potsmaster/openstack-manuals,kairoaraujo/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,openstack/openstack-manuals,gongysh2004/openstack-manual,Akasurde/openstack-manuals,Akasurde/openstack-manuals,openstack/openstack-manuals,saeki-masaki/openstack-manuals,saeki-masaki/openstack-manuals