Update changelog for 0.14.0.
Bump version to 0.14.0.

Changes:

* Install dependencies via Puppet. (andytinycat)
* Add install-deps action to install dependencies. (andytinycat)
* Fix log message. (ryansch)
* Add a `patch` helper method to apply patches. (piavlo)
* Support for Omnibus-style packaging. (andytinycat)
* Add recipe to build a fat (omnibus-style) package for fpm-cookery.
* Add `:args` option for the curl handler. (torrancew)
* Add `-V` command line option to show fpm-cookery and fpm versions.
Depend on minitest 4.x.