title: step-by-step guide slim-lang installation into my editor
body: <p>I like to try to use slim in my new project,however I am unsure of how to make slim 'appear' in my notepad ++.After a search , I found that there is a template in github. However I do not know how to install slim as a gem.I got stuck with this code.</p>
  
  <p><code>gem install slim</code>.</p>