title: Get the unique values from two arrays and put them in another array
body: <p>I have two arrays in javascript -:</p>
  
  <pre><code>var array1 = ['12','1','10','19','100'];
  var array2 = ['12','10','19'];
  </code></pre>
  
  <p>I need to a method to get the unique from two arrays and put them in array3
  <code>Array3</code> should be -: </p>
  
  <pre><code>var array3 = ['1','100'];
  </code></pre>
  
  <p>Thanks for help. </p>