Currently, Zaqar is holding the user related guide as xml format,
which is hard to maintain. Until now, we have moved the config
ref to rst and the API ref is happening as well. So it would be
nice if the user getting started guide can be coverted to rst
as well. This patch does it and removes the old docbook files.
Change-Id: Ib74fb49ba2a5b2c1dea9c6bd75406d804504d392
5a901c2815