Update ssh configuration doc
Update ssh configuration doc

The main idea of this update is to make the configuration process
easier to read and follow.

Change-Id: I73cf811415900eaf99673de16f83ea7c9da16045

mikalstill/nova,rahulunair/nova,openstack/nova,mahak/nova,mikalstill/nova,gooddata/openstack-nova,gooddata/openstack-nova,openstack/nova,mikalstill/nova,klmitch/nova,mahak/nova,rahulunair/nova,gooddata/openstack-nova,gooddata/openstack-nova,klmitch/nova,openstack/nova,rahulunair/nova,klmitch/nova,klmitch/nova,mahak/nova