Good lord this thing needed some love. This change
does a few things:
* Remove the duplicate man page.
* Rename some titles to drop the CINDERCLIENT yelling -
this is docs about cinderclient, I get it, no need to
repeat in all caps.
* Fixed the sub-section title formatting in the home page.
* Dropped the duplicate usage guide wording and simply linked
to the user docs from the home page.
Change-Id: I259787a40151e8c875ad87021f655a141e06b15e