Move packages section earlier

For SLES, RabbitMQ is part of the OpenStack repo, we thus need to
setup the Havana repository first before we can install RabbitMQ.

Closes-Bug: #1241190
Backport: stable/havana

Change-Id: I060606326134449cf582549fa68fa26f61171b75
Fix Docker file reference

As reported by Ming Fang, the Configuration Reference
section on docker was instructing users to update the
wrong configuration file. This patch fixes it to the
correct one

Closes-Bug: 1241915

Change-Id: Ib425e7a1c0886fcef9373de0953a66dbded0cd6d
Backport: stable/havana
Modified GitIgnore File for Vagrant

Added a few entries to ignore vagrant related files. These files
can tend to be heavy and are not required to be the part of the
source.
Removed Vagrant from the .gitignore. Thanks Trevor

bp/training-manuals

Change-Id: Icb89d49566367adcd4db5fe412914d852c22830b
Updated Neutron Section

I wish I could say that Neutron Installation section is 100% done,
here is the list of things that need to be finished/completed/considered:

1. Need someone to proof read it once.
2. Add sections for other OpenStack Neutron Plugins, only OVS is
covered over here.
3. Need to review the design of the Networking Section, I think it
can be presented better than it is as of now, as its pretty much
confusing to jump through various modes/types of installation
related to networking section(s).

Backport: stable/havana

Change-Id: Icba8970f3e1340b4b84f7b69831fe9f4b2c03384
Merge "Updated Neutron Section"
Merge "Modified GitIgnore File for Vagrant"
Merge "Move packages section earlier"
Merge "Fix Docker file reference"