title: mac os sierra pod install command failure
body: <p>After moving to Mac OS Sierra, I'm facing problem to install cocoapods.</p>
  
  <ol>
  <li><p>Every time I run <code>sudo gem install cocoapods --pre</code> every thing installed well, but while trying to install a pod, the terminal stack on Setting up CocoaPods master repo. Already updated the system with <code>sudo gem update --system</code> and still got the same issue, searched online to found old answers to use <code>pod install --verbose  Ss</code>. I found in THIS answer fail again tells to install it manually.<br>
  NOTE: I have the latest version of 'Command Line Tools'. Any suggestion or how to install master repo manually?</p></li>
  <li><p>Even when empty pod (i.e. without any pod name in it) is installed it gives</p></li>
  </ol>
  
  <pre>
  /Library/Ruby/Site/2.0.0/rubygems/dependency.rb:315:in `to_specs': Could not find 'cocoapods' (>= 0) among 66 total gem(s) (Gem::LoadError)
  Checked in 'GEM_PATH=/Users/my_name/.gem/ruby/2.0.0:/Library/Ruby/Gems/2.0.0:/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0', execute `gem env` for more information
      from /Library/Ruby/Site/2.0.0/rubygems/dependency.rb:324:in `to_spec'
      from /Library/Ruby/Site/2.0.0/rubygems/core_ext/kernel_gem.rb:64:in `gem'
      from /usr/local/bin/pod:22:in `'
  </pre>