Do not vendor cookbooks using Berkshelf anymore

Instead, use the Berkshelf support in knife-solo and the
vagrant-berkshelf plugin on Vagrant

cookbooks/hostname/metadata.rb

@@ -1,20 +0,0 @@
-# -*- coding: utf-8 -*-
-
-name             'hostname'
-maintainer       'Maciej Pasternacki'
-maintainer_email 'maciej@3ofcoins.net'
-license          'MIT'
-description      'Configures hostname and FQDN'
-long_description IO.read(File.join(File.dirname(__FILE__), 'README.md'))
-version          '0.4.2'
-
-supports 'debian'
-supports 'ubuntu'
-supports 'freebsd'
-
-depends 'hostsfile'
-
-source_url 'https://github.com/3ofcoins/chef-cookbook-hostname' if respond_to?(:source_url)
-issues_url 'https://github.com/3ofcoins/chef-cookbook-hostname/issues' if respond_to?(:issues_url)
-
-chef_version '>= 12.1' if respond_to?(:chef_version)