Test: kitchen user should be able to 'mco ping'

At present, this fails as the mcollective connector configuration is
only readable by root.
Add attribute: users authorised to use mcollective.
Add an 'mcollective' group to the system.
Add specified users to the 'mcollective' group'
Set correct permissions on connector configs.

This will allow members of the mcollective group to use mco without
sudo.
Move specs to correct file.

Many of the assertions in the server spec should have been in the
common spec, as that's the recipe that implements them.
Set correct permissions on the redis config.
Add 'kitchen' as mco user for integration tests

This allows busser to run mcollective commands without using sudo.
Parameterise mcollective group name.
Add specs for ::client recipe.
Tighten permissions on client.cfg

The client config may contain sensitive information, so restrict it to
users in the mcollective group.
Fix rabbitmq integration test.
Release 0.14.0

Introduces an mcollective group, to allow limited use of mco by
regular users without exposing configuration to the world.