title: Comparing two arrays ignoring element order in Ruby
body: <p>I need to check whether two arrays contain the same data in any order.
  Using the imaginary <code>compare</code> method, I would like to do:</p>
  
  <pre><code>arr1 = [1,2,3,5,4]
  arr2 = [3,4,2,1,5]
  arr3 = [3,4,2,1,5,5]
  
  arr1.compare(arr2) #true    
  arr1.compare(arr3) #false
  </code></pre>
  
  <p>I used <code>arr1.sort == arr2.sort</code>, which appears to work, but is there a better way of doing this?</p>