Refactor userguide "Yardstick Installation"
[1] must be refactored in order to:
* Include proxy options.
* Use OpenStack client, instead of project CLI.
* Use sudo in some commands.
* Adapt the document to rst coding style.
* Fix minor errors.
JIRA: YARDSTICK-828
[1] https://github.com/opnfv/yardstick/blob/
923aa1738cbf5a8053e77e00937fc26f2142f6a3/docs/testing/user/userguide/04-installation.rst
Change-Id: Ice63f344a8a87221bdf4daa6153b9ccac321e5b7
Signed-off-by: Rodolfo Alonso Hernandez <rodolfo.alonso.hernandez@intel.com>
(cherry picked from commit
d20b876a02904653cf390a97c2ed9973821dc508)