Remove a DB query for get_ports_by_node()

This renames get_ports_by_node() to get_ports_by_node_id() and changes
the node_id argument to always need to be the integer ID. This removes
the need for get_ports_by_node() to query the DB for UUID -> ID
conversion.

By doing this, we can save a DB query in the cases where we already have
the Node integer ID.

This is needed to help set up the next patch to clean up calls to
get_node(). There's now a case in port API controller where we need
to lookup the Node by UUID just to get its ID to be passed into this
call. Until we implement the Node lazy-loading code, we fetch the
full Node, but this isn't any worse than before for this case, as
I'm just moving it from the DB layer. I've noted this with a FIXME
and it will be made more efficient in the future.

Change-Id: I9993c0c87794171fb971524ac5c30490b3e33716
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"
Merge "Remove a DB query for get_ports_by_node()"
Install guide for Ironic

This contains the beginnings of documentation on how to
install and configure the Bare Metal Service (ironic).

This is modelled after documentation available at
http://docs.openstack.org/havana/install-guide/install/apt/content/.

Change-Id: I7bf0a9caaf5bd5a2fcfc6fd0b0addeedb7ca26cb