title: Unable to git clone , Failed to connect to github.com port 443: Network is unreachable
body: <pre><code>git clone https://github.com/plataformatec/devise.git
  </code></pre>
  
  <p>generates error</p>
  
  <pre><code>fatal: unable to access 'https://github.com/plataformatec/devise.git/': Failed to connect to github.com port 443: Network is unreachable
  </code></pre>
  
  <p>I am using a personal tata photon connection and ubuntu 14.04 LTS , I am new to git and any help is welcome ...</p>