title: Convert list of dictionaries to a pandas DataFrame
body: <p>How can I convert a list of dictionaries into a <code>DataFrame</code>? Given:</p>
  <pre><code>[{'points': 50, 'time': '5:00', 'year': 2010}, 
   {'points': 25, 'time': '6:00', 'month': &quot;february&quot;}, 
   {'points':90, 'time': '9:00', 'month': 'january'}, 
   {'points_h1':20, 'month': 'june'}]
  </code></pre>
  <p>I want to turn the above into a <code>DataFrame</code>:</p>
  <pre><code>      month  points  points_h1  time  year
  0       NaN      50        NaN  5:00  2010
  1  february      25        NaN  6:00   NaN
  2   january      90        NaN  9:00   NaN
  3      june     NaN         20   NaN   NaN
  </code></pre>
  <p>Note: Order of the columns does not matter.</p>