title: Javascript - Add a comma after every line break
body: <p>I have a .txt file full of strings that look like the ones beneath.
  I need to add a comma at the end of every line.
  At the moment it looks like this:</p>
  
  <pre><code>name,age ----&gt; usa
  name,age ----&gt; uk
  name,age ----&gt; de
  </code></pre>
  
  <p>And after it should look like this:</p>
  
  <pre><code>name,age ----&gt; usa,
  name,age ----&gt; uk,
  name,age ----&gt; de,
  </code></pre>