title: Convert "String" of Binary to NSString of text
body: <p>I am able to convert an NSString of (ASCII) text to a NSString of binary numbers, but I am having troubles doing the opposite. For example: "Hi" becomes "01101000 01101001".</p>
  
  <pre><code>I need: "01101000 01101001" to become "Hi".
  </code></pre>
  
  <p>I'm looking for the most <i>direct</i> way to implement this. Note the space between every 8 bits of binary numbers.</p>