title: NVM giving error while doing nvm ls
body: <p>I was trying to install and switch between node version, so i first install nvm using below</p>
  
  <pre><code>Administrators-MacBook-Pro:~ user.name$ sudo npm install nvm -g
  Password:
  npm http GET https://registry.npmjs.org/nvm
  npm http 304 https://registry.npmjs.org/nvm
  npm http GET https://registry.npmjs.org/mkdirp
  npm http 304 https://registry.npmjs.org/mkdirp
  /usr/local/bin/nvm -&gt; /usr/local/lib/node_modules/nvm/bin/nvm
  nvm@0.0.1 /usr/local/lib/node_modules/nvm
  └── mkdirp@0.3.5
  </code></pre>
  
  <p>After this i was trying to do "nvm ls" to list node version but it gave me an error(below). <strong>Please advice what's wrong with it</strong></p>
  
  <pre><code>Administrators-MacBook-Pro:~ user.name$ nvm ls
  
  module.js:340
      throw err;
            ^
  Error: Cannot find module '/usr/local/lib/node_modules/nvm/bin/nvm-ls'
      at Function.Module._resolveFilename (module.js:338:15)
      at Function.Module._load (module.js:280:25)
      at Module.require (module.js:364:17)
      at require (module.js:380:17)
      at Object.&lt;anonymous&gt; (/usr/local/lib/node_modules/nvm/bin/nvm:15:1)
      at Module._compile (module.js:456:26)
      at Object.Module._extensions..js (module.js:474:10)
      at Module.load (module.js:356:32)
      at Function.Module._load (module.js:312:12)
      at Function.Module.runMain (module.js:497:10)
  </code></pre>