title: Remove folder from git but fatal outside repository error while already pushed
body: <p>I am using AWS Cloud9</p>
  
  <p>I was fiddling around installing/updating nvm in my git repo and then afterwards I git pushed everything to my Github repo. However, it also pushed the nvm library onto there (hundreds of files). Now in my Github repo, there is a folder called "/home/ec2-user/.nvm" which I want to delete. </p>
  
  <p>However, if I go into my git repo to delete it, it says:</p>
  
  <p><code>ec2-user:~/rails_projects/alpha-blog (master) $ git rm -r /home/ec2-user/.nvm
  fatal: /home/ec2-user/.nvm: '/home/ec2-user/.nvm' is outside repository</code></p>
  
  <p>if I just do <code>rm -rf "/home/ec2-user/.nvm</code> nothing really happens. </p>
  
  <p>Any idea what happened and how I can delete it from my Github repo?</p>