title: Showing all index values when using multiIndexing in Pandas
body: <p>I would like that when viewing my DataFrame I will see all values of the multiIndex, including when subsequent rows have the same index for one of the levels. Here is an example:</p>
  
  <pre><code>arrays = [['20', '50', '20', '20'],['N/A', 'N/A', '10', '30']]
  tuples = list(zip(*arrays))
  index = pd.MultiIndex.from_tuples(tuples, names=['Jim', 'Betty'])
  pd.DataFrame([np.random.rand(1)]*4,index=index)
  </code></pre>
  
  <p>The output is:</p>
  
  <pre><code>                                0
  Jim         Betty           
  20          N/A          0.954973
  50          N/A          0.954973
  20          10           0.954973
              30           0.954973
  </code></pre>
  
  <p>I would like to have a 20 also in the south-west corner. That is, I would like my DataFrame to be:</p>
  
  <pre><code>                                0
  Jim         Betty           
  20          N/A          0.954973
  50          N/A          0.954973
  20          10           0.954973
  20          30           0.954973
  </code></pre>
  
  <p>Is Pandas capable of doing that?</p>