title: Overloading ActiveSupport's default to_sentence behaviour
body: <p>ActiveSupport offers the nice method <code>to_sentence</code>. Thus,</p>
  
  <pre><code>require 'active_support'
  [1,2,3].to_sentence  # gives "1, 2, and 3"
  [1,2,3].to_sentence(:last_word_connector =&gt; ' and ')  # gives "1, 2 and 3"
  </code></pre>
  
  <p>it's good that you can change the last word connector, because I prefer not to have the extra comma. but it takes so much extra text: 44 characters instead of 11!</p>
  
  <p><strong>the question</strong>: what's the most ruby-like way to change the default value of <code>:last_word_connector</code> to <code>' and '</code>?</p>