[chef] chef-runner v0.6.0

[Mathias Lafeldt < >]

Ohai Chefs!

chef-runner v0.6.0 is out!

https://github.com/mlafeldt/chef-runner/releases/tag/v0.6.0

FEATURES:

* Add ability to install Chef before provisioning. This allows you to,
for example, provision bare servers that have nothing installed but
the base operating system. For this, use the new `-i` option (or
`--install-chef`).

* Add support for Berkshelf v3 in addition to v2. (Thanks to
@arosenhagen for the original pull request!)

* Re-add long option names like `--host` and `--json-attributes`.
Those were removed when porting chef-runner to Go (v0.2.0).

* Re-add ability to install chef-runner via Homebrew.

IMPROVEMENTS:

* Add Quick Start guide to README.

* Only prepend `bundle exec` to Ruby commands if Bundler is actually
installed. A Gemfile alone is no longer enough.

* Add basic Godoc documentation to all parts of the source code. As a
result, golint no longer reports any coding style issues.

* Run golint style checks on Travis CI.

BREAKING CHANGES:

* Change default output format of Chef from `null` to `doc`. The
former is the default used by Vagrant, while the latter is the actual
default of Chef Solo.


Enjoy!

-Mathias