title: In Rails, display time between two dates in English
body: <p>In a Rails project I want to find the difference between two dates and then display it in natural language.  Something like</p>
  
  <pre><code>&gt;&gt; (date1 - date2).to_natural_language 
  "3 years, 2 months, 1 week, 6 days"
  </code></pre>
  
  <p>Basically <a href="https://stackoverflow.com/questions/979468/date-difference-in-english">this</a> for ruby.  </p>
  
  <p>Google and the Rails API haven't turned up anything.  I've found some things that will give you the difference in one unit (ie, how many weeks between two dates) but not something that will accurately calculate years, months, weeks, days all together.  </p>