Add a set of computed defaults for a couple of known platform names.

Currently given these platform names, the image and platform values can
be auto-generated:

* ubuntu-12.04
* centos-6.4
Merge pull request #19 from fnichol/computed-defaults

Add a set of computed defaults for a couple of known platform names.
default_image rewrite, version bump (beta)
version bump, less boiler plate
https://github.com/portertech/kitchen-docker/graphs/contributors
force /sbin/initctl symlink, minor version bump
[remote] docker socket config, remote docker
[remote] use 22/tcp forwarding for container ssh
[remote] moved 22/tcp forwarding out of config[:forward], ssh port on 0.0.0.0
[remote] document socket in readme
[remote] fixed container id parsing for docker 0.7
version bump
Merge pull request #21 from portertech/remote

Support remote Docker
no need for sudo in provision_command
Update to support the docker "hostname" command flag

* This also includes addition to the readme and fixing another readme
  typo
Merge pull request #22 from petecheslock/master

Update to support the docker "hostname" command flag
Added option privileged_mode which defaults to false to remain
consistent with the current functionality. Setting this to true in
.kitchen.yml will pass the -privileged=true flag to docker.
Updated README.md with info about the additional option
Modified option to just be :privileged, simpler
Merge pull request #23 from adnichols/add_privileged_mode

Added option privileged which defaults to false
pre-release cleanup