title: Create a data frame with date as column names
body: <p>I would like to construct a data table in R that has columns as dates and rows as times (without date info). Basically I have a table in the form:</p>
  
  <pre><code>Time  21.04.15 22.04.15 24.04.15 03.05.15
  00:00      0.4      0.4      0.4      0.4
  01:00      0.4      0.4      0.4      0.4
  02:00      0.4      0.4      0.4      0.4
  03:00      0.6      0.6      0.6      0.6
  04:00      0.6      0.6      0.6      0.6
  05:00      0.7      0.8      0.8      0.8
  06:00      0.7      0.8      0.8      0.8
  07:00      0.7      0.8      0.8      0.8
  ...
  </code></pre>
  
  <p>I would like to address (plot, extract) the columns by date and elements by date and time.</p>
  
  <p>Is this possible?</p>