title: Creating pandas DataFrame from multiple csv files with date index
body: <p>I have multiple csv files with measurement data, that I would need to merge into one Pandas DataFrame with the date/time as index. I have tried using pd.concat, however, this only adds the csv files together and does not 'sort' them correctly.</p>
  
  <p>Example file 1:</p>
  
  <pre><code>    NAME;DATE;VALUE;UNIT
      SO.DA.TT.401.3;01-01-2015 00:00:00;14,9;°C
      SO.DA.TT.401.3;01-01-2015 00:10:00;14,9;°C
  </code></pre>
  
  <p>Example file 2:</p>
  
  <pre><code>    NAME;DATE;VALUE;UNIT
      SO.DA.TT.401.3;16-06-2014 20:50:00;51,9;°C
      SO.DA.TT.401.3;16-06-2014 21:00:00;51,8;°C
  </code></pre>
  
  <p>How can I import the files such that they are sorted both by index and name into one DataFrame??</p>