title: Cannot install vagrant-berkshelf plugin
body: <p>I've updated to Vagrant 1.4.3 and am attempting to install the vagrant-berkshelf plugin. I'm getting the following error:</p>
  
  <pre><code>$ vagrant plugin install vagrant-berkshelf
  Installing the 'vagrant-berkshelf' plugin. This can take a few minutes...
  /opt/vagrant/embedded/lib/ruby/2.0.0/rubygems/installer.rb:184:in `check_executable_overwrite': "minitar" from minitar conflicts with installed executable from archive-tar-minitar (Gem::InstallError)
  from /opt/vagrant/embedded/lib/ruby/2.0.0/rubygems/installer.rb:384:in `block in generate_bin'
  from /opt/vagrant/embedded/lib/ruby/2.0.0/rubygems/installer.rb:371:in `each'
  from /opt/vagrant/embedded/lib/ruby/2.0.0/rubygems/installer.rb:371:in `generate_bin'
  from /opt/vagrant/embedded/lib/ruby/2.0.0/rubygems/installer.rb:231:in `install'
  from /opt/vagrant/embedded/lib/ruby/2.0.0/rubygems/dependency_installer.rb:379:in `block in install'
  from /opt/vagrant/embedded/lib/ruby/2.0.0/rubygems/dependency_installer.rb:339:in `each'
  from /opt/vagrant/embedded/lib/ruby/2.0.0/rubygems/dependency_installer.rb:339:in `each_with_index'
  from /opt/vagrant/embedded/lib/ruby/2.0.0/rubygems/dependency_installer.rb:339:in `install'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/plugins/commands/plugin/action/install_gem.rb:65:in `block in call'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/plugins/commands/plugin/gem_helper.rb:42:in `block in with_environment'
  from /opt/vagrant/embedded/lib/ruby/2.0.0/rubygems/user_interaction.rb:40:in `use_ui'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/plugins/commands/plugin/gem_helper.rb:41:in `with_environment'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/plugins/commands/plugin/action/install_gem.rb:52:in `call'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/lib/vagrant/action/warden.rb:34:in `call'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/plugins/commands/plugin/action/bundler_check.rb:20:in `call'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/lib/vagrant/action/warden.rb:34:in `call'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/lib/vagrant/action/builder.rb:116:in `call'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/lib/vagrant/action/runner.rb:69:in `block in run'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/lib/vagrant/util/busy.rb:19:in `busy'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/lib/vagrant/action/runner.rb:69:in `run'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/plugins/commands/plugin/command/base.rb:17:in `action'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/plugins/commands/plugin/command/install.rb:27:in `execute'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/plugins/commands/plugin/command/root.rb:56:in `execute'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/lib/vagrant/cli.rb:38:in `execute'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/lib/vagrant/environment.rb:484:in `cli'
  from /opt/vagrant/embedded/gems/gems/vagrant-1.4.3/bin/vagrant:127:in `&lt;top (required)&gt;'
  from /opt/vagrant/bin/../embedded/gems/bin/vagrant:23:in `load'
  from /opt/vagrant/bin/../embedded/gems/bin/vagrant:23:in `&lt;main&gt;'
  </code></pre>
  
  <p>I tried to manually install minitar with both the system and Vagrant-specific rubies. System ruby installed it just fine. When I manually installed it into the Vagrant ruby, I got the following:</p>
  
  <pre><code>$ sudo /opt/vagrant/embedded/bin/gem install minitar
  Fetching: minitar-0.5.4.gem (100%)
  minitar's executable "minitar" conflicts with archive-tar-minitar
  Overwrite the executable? [yN]  y
  Successfully installed minitar-0.5.4
  Parsing documentation for minitar-0.5.4
  Installing ri documentation for minitar-0.5.4
  1 gem installed
  </code></pre>
  
  <p>But, I still get the exact same error. I've tried to manually install every gem in the Gemfile from the vagrant-berkshelf github repo and still cannot install.</p>