title: Pandas reset index on series to remove multiindex
body: <p>I created a <code>Series</code> from a <code>DataFrame</code>, when I resampled some data with a count
  like so: where <code>H2</code> is a <code>DataFrame</code>:</p>
  
  <pre><code>H3=H2[['SOLD_PRICE']]
  H5=H3.resample('Q',how='count')
  H6=pd.rolling_mean(H5,4)
  </code></pre>
  
  <p>This yielded a series that looks like this:</p>
  
  <pre><code>1999-03-31  SOLD_PRICE     NaN
  1999-06-30  SOLD_PRICE     NaN
  1999-09-30  SOLD_PRICE     NaN
  1999-12-31  SOLD_PRICE    3.00
  2000-03-31  SOLD_PRICE    3.00
  </code></pre>
  
  <p>with an index that looks like:</p>
  
  <pre><code>MultiIndex
  [(1999-03-31 00:00:00, u'SOLD_PRICE'), (1999-06-30 00:00:00, u'SOLD_PRICE'), (1999-09-30 00:00:00, u'SOLD_PRICE'), (1999-12-31 00:00:00, u'SOLD_PRICE'),.....
  </code></pre>
  
  <p>I don't want the second column as an index. Ideally I'd have a <code>DataFrame</code> with column 1 as "Date" and column 2 as "Sales" (dropping the second level of the index). I don't quite see how to reconfigure the index.</p>