Add Ironic User Guide

Add a User guide, Initial chapters to cover introduction, architecture
diagrams, terminology for Ironic service.

Change-Id: I08faac6204aa412e330362133eb14241f3c21b34
Sync oslo/config/generator

Sync from oslo:
  0e98afda1ba85243771e31e0c859d550334da648

Change-Id: I9162975b4b76a61693262819a291cc9fa9d2c318
Overwriting node_is_available in IronicDriver

Overwriting node_is_available so it call to
node.get from the ironic client.

Change-Id: If27048342349c6eb87291416d82f719001db6dac
Closes-Bug: #1299288
Fix conductor.manager test assertion order

A bunch of conductor.manager tests have equaltiy assertions in the
wrong order: this patch addresses that.

Change-Id: I88f3a7a05e7c4f3e1d0cd86afc5167e9e73bf4af
Imported Translations from Transifex

Change-Id: I8ab062a641f899577b0b885e1d519b3db085966d
Merge "Overwriting node_is_available in IronicDriver"
Merge "Sync oslo/config/generator"
Merge "Imported Translations from Transifex"
Merge "Add Ironic User Guide"
Merge "Fix conductor.manager test assertion order"