title: matplotlib plot datetime in pandas DataFrame
body: <p>I have a pandas DataFrame that looks like this <code>training.head()</code></p>
  
  <p><img src="https://i.stack.imgur.com/G5PWJ.png" alt="enter image description here"></p>
  
  <p>The DataFrame has been sorted by date. I'd like to make a scatterplot where the date of the campaign is on the x axis and the rate of success is on the y axis. I was able to get a line graph by using <code>training.plot(x='date',y='rate')</code>. However, when I changed that to <code>training.plot(kind='scatter',x='date',y='rate')</code> I get an error: KeyError: u'no item named date'</p>
  
  <p>Why does my index column go away when I try to make a scatterplot? Also, I bet I need to do something with that date field so that it doesn't get treated like a simple string, don't I?</p>
  
  <p>Extra credit, what would I do if I wanted each of the account numbers to plot with a different color?</p>