minor fixes for 2017/2018 vision document
minor fixes for 2017/2018 vision document

Change-Id: I20a7d69f89c840c394f8c6482602cca50f71f645
Signed-off-by: Doug Hellmann <0798ebecfb7bc4dfb9d0445c2fa030eb64e1fa1c@doughellmann.com>

openstack/openstack-manuals,openstack/openstack-manuals,openstack/openstack-manuals,openstack/openstack-manuals